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Digital Atmosphere help - Weather Graphics Technologies

1. STORM PREDICTION CENTER NWS NCEP NORMAN OK DAY 2 CONVECTIVE OUTLOOK REF AWIPS GRAPHIC PGWI47 KWBC VALID 051200Z 0612002 THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 40 ESE P07 BGS CDS 55 NE AMA EHA LAA GLD HLC SLN CNU SGF JBR MKL TUP LUL 35 SE HUM CONT 30 S CRP 25 S LRD GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 30 ENE ELO 50 NW EAU DBQ HUF LUK HTS TRI 65 S TYS ATL ABY AQQ CONT 40 SW DMN 50 WNW ONM GUP 60 ESE PGA U17 VEL 45 NNE CAG CYS SNY ANW JMS 70 NNE DVL MODELS INDICATE UPPER CLOSED LOW OVER NORTHERN BAJA WILL EVOLVE INTO A SHORT WAVE TROUGH AND ACCELERATE EASTWARD INTO THE SOUTHERN PLAINS SUNDAY SUNDAY NIGHT THIS IS IN RESPONSE TO VIGOROUS NORTHERN BRANCH SHORT WAVE TROUGH NOW OVER THE PACIFIC NORTHWEST AND PROGGED TO CONTINUE TO DIG INTO THE CENTRAL ROCKIES BEFORE SHIFTING EASTWARD INTO THE CENTRAL PLAINS AS THESE SYSTEMS INTERACT AND UPSTREAM SHORT WAVE DIGS ACROSS THE NORTHERN PACIFIC COAST INTO THE GREAT BASIN MODELS INDICATE EVOLUTION OF LONG WAVE Digital Atmosphere 8 8 8 9 8 10 Radar Allows you to plot echoes and attribute data from radar messages Digital Atmosphere can import radar data from one of two sources e Old style MDR data from RAR
2. Workchart Popup window Identify warning Get lat long Show sounding Erase markings Turn off roam Ready Status bar MAN Z Digital Atmosphere 5 2 5 3 5 4 Main menu The main menu is where you issue most commands for Digital Atmosphere This dropdown menu structure works just like most other Windows programs Each main menu command will be described in the following chapters in this manual so we won t discuss them in detail at this time Speed buttons toolbar Speed buttons The speed buttons are provided as a convenient way of accessing frequently used main menu commands You can find the meaning of each one by simply resting the cursor on a button a popup hint will appear Each button corresponds to a main menu command summarized as follows going left to right To get more information go to the following chapters to see what the main menu command does Py Import a file Accomplishes the same thing as File gt Import file e Import a directory File gt Import directory iol Load a map Map gt Load Map Bl Erase workchart Map gt Erase Map ES Data plot Data gt Data Plots Internet retrieval Internet gt Retrieve Data El Print File gt Print os Quality control File gt Quality Control Calculator File gt Calculator T Warnings Data gt Warnings Preferences File gt Preferences Generate map This presents a list of geographical locations tha
3. Dotted Plots latitude longitude as a series of dotted lines Page 61 Digital Atmosphere 15 4 4 Grid Interval Grid interval fi 0 deg If a latitude longitude map is plotted this value controls what interval will be used in degrees to plot the grid A value of 1 5 10 or 15 should normally be used So that the grid wraps uniformly around the globe the value you select should divide evenly into 360 15 4 5 Default Size Default size pixels Width 640 Height 450 When you use quick mapmaking commands such as Generate Map on the speed button toolbar this determines what the map size will be in pixels 15 4 6 Map element settings Background color Plots text and contours Coastlines Main Highways Roads and custom lines Counties MA T water body fill color a IV Lationg grids ea V International boundaries a IV State boundary outline IV Island outline FT River outline E V Lake outline i Use this table to set which geographical features you want displayed and in what color Remember that these will not take effect until the next time you generate a map Page 62 Digital Atmosphere 15 5 15 5 1 15 5 2 Station plots Station plots tab Also see the special topics on Surface plot models Upper air plot models and Station filtering V Plot radar status labels Plot radar status labels Whenever Overlay Radar is chosen this determines whether
4. 3394 Laurel Ft Meade Road Laurel MD 20724 301 725 1212 http www weathernode com Offers the very popular WeatherNode software and demodulator satellite downlink equipment for GOES and so on Zephyrus Electronics Ltd 171 S 122 E Avenue Tulsa OK 74128 2405 918 437 3333 http www big Digital Atmosphere z com Contact Ed Covington for radio and satellite downlink equipment and packages including the WX 1 VHF radio receiver and WeatherNode software WX 11 system and software for GOES 8 9 with antenna WX 21 system and software for Galaxy 4 with antenna WX 31 SCA radio receiver and WeatherNode software and WX 41 Demodulator and WeatherNode software SkyWalker Data Systems Inc 7303 West 35th Str Tulsa OK 74107 918 445 1488 www skywin com Sells software and demodulators satellite downlink equipment for GOES and EMWIN rebroadcast equipment They also have a nice web site dedicated to EMWIN efforts Swagur Enterprises P O Box 620035 Middleton WI 53562 0035 608 592 7409 http www execpc com swagur Offers satellite downlink equipment for GOES along with Maryland Radio Center merchandise Wilmanco 5350 Kazuko Court Moorpark CA 93021 805 523 2390 Contact Deke Williams for EMWIN product information satellite downlink equipment for GOES etc Handie Base and More Inc 27270 E 75th St S Broken Arrow OK 74104 918 357 2139 Sells Zephyrus Weather Info Net Receivers hardware and software and
5. Minor enhancements to tracking of metric vs English units for purposes of product labelling Added COM4 to COM8 in EMWIN Ingest Allows up to 1000 stations in DIGATMOS PRI priority table Adds Map gt Import command to allow satellite photos etc to be underlaid Map gt Generate By Lat Lon now allows latitude longitude and zoom to be numerically tweaked and advanced settings to be reset with one button click Enhanced fills for Australia Script timer has been renamed to Scheduler Scheduler now allows multiple script names along with the usual multiple execution times documentation has been added in this manual under Appendix Scripting Digital Atmosphere now caches a map as soon as it is created so that it will be available on reloading Digital Atmosphere this applies both in Generate by Lat Long and Generate dropdown menu Vorticity and divergence now color appropriately as in earlier versions with inverted shades for negative divergence A solid zero line has also been added Divergence and vorticity have now been added to the Analysis gt Wind menu for more convenient access Divergence has been recalibrated and plots in 10 6 m 2 A bug in the scripting which prevented wind analysis grids and streamlines from plotting is now fixed BETA 1 21 01 FIXES Problem with Map gt Save in 1 20 01 release fixed Conflict with Alt shortcut keys for main menu fixed Added script command SFCPLOTMODEL for loading surface plot
6. A A A fewee eats tes 74 15821 CON O NS tab ii da dd dada 74 15 9 Miscellaneous A id dat 75 AA E AA OT 75 16 TFOUDIESNOO UN Ori cti 78 16 1 Howto solvea problenm iiia iare anae deanar edanan darea vase eaten Saad echt eet els 78 A dios 79 TAETEMNOIOIY 2 ia 79 17 2 Map attribute file structure nics cfs a odas 80 Eee iTar EAE T AT A T A ese 81 17 4 Using tabular weather data cccccesssseeeeeeeeeeeeeseeeeneeeeeeeeeseseneeeeeeeeeeeeeeneeeeeeeeeeseeaseeeeeeeeeeeeeeseeesenens 86 17 5 Using exported analysis gridS 0 ees hewtaleene sd ece tea el tian hse cats octoitenentacedestabwcevnensehccwes 88 SFOs VIN once es Aaah A ce a de od ee de ae ed a aceasta de cee ee der osetia 89 17 7 About weather data ii ia do 93 17 9 Raw data Samples a o cee SS ara e a tea eee 94 17 9 Version Change SUI ANI GS 2035 5 ice eea a aa dake cake eases sale aA E AK ad Mesi asrda iae Kaa iaia a 96 LLL 8 5 A ar rer aAa Aa Ee ae a aeaa ea eae rana aae Aaaa einai 109 Page V Digital Atmosphere 1 Title page Digital Atmosphere USER S GUIDE September 2001 Version 2000 1 1 Software and documentation copyright 1995 2000 Tim Vasquez Weather Graphics Technologies All rights reserved All major changes since the last version are highlighted in red Documentation Tim Vasquez and Shannon Key Weather Graphics Technologies P O Box 450211 Garland Texas 75045 0211 888 388 0070 405 573 0700 Fax 405 329 5275 Customer Service
7. A A eek ete eee nies eh ego ein he tek apelin 19 7 Map CommandS csoisniciiiaciii dicci n 20 Ts Vex INTRO GUI CUO IN ii 20 EAE a o 20 Digital Atmosphere pace cil pl acess ccs A et ee ee etic cattk eth ees vet auet adders 20 4 Generate Map BY LAU sce wetcreda vel otis wc ieee eel enaren aa aa de e aa adaa iaa deel ule ehcine eed 21 FB Generate Map Dy Staton scsi oie eee e arae eaaa ae es ia eo esac cee dae okt ted eee cest eet aian AEEA 22 20 090 MAD ii ti 22 A O 23 TO EXPO MAS Ce PSE Er a REE Pe ere one 23 ED RVING A O E A a ee de a ee secede een Ma 24 TAO IOMA a oth ath este Sia ates te ads he ete alt eee 24 ea TOU COMMER orice ek ace chia eh ae ed eed occa ee eh eer ae hho 25 1 12 GOpy to clipboard iisa eats as tein eas cic cna Scanned es eee alta eee aloe 25 aos WMIAKOAODOG FAD IVY can a ae a A a ce ald hss aaah ce T 26 1 14 Photoreal topography Sii di 26 Messy PNG AS CIN e e a 27 TWO e o UN o A 27 ples PROG CUES A o iia 27 7 18 Add COURUES i Someta cesses Sete tea st cea ald ead ig ett Eaa aaa Sian aa tetas ease eat aaa daana 28 TTILADO MIG WAYS 6 tela A ies ae eee haa ae EA 28 7 20 AGG secondary WIGHWAY Ss ii A iaai 28 Pe VSG CUSTONI OVEN AY Ss certs fetes Reach A A TS 28 1 22 Add date Stamp cc A Ai Pee ariel PnP ere 28 8 Data CO insta 29 Dl AAA A nn A A eee PERE een ee eee PEE eee 29 2 SCUSTON data PIOUS inanan A A A 29 E TADIG IONS iso aioe ia fees ea ae es eles ea cas cido cae ane 30 OAc Televisi n plots iintindi k
8. Pressure height Menu iii dan 39 DO HO A aae naia i Ea S iiaae ia iao ENAN 39 9 6 2 Press re TENGEN OV cisne rar 39 9 6 3 Altimeter Setting a r A Rai 39 9 6 4 Sea level PreSSUne panas 39 9 6 5 Isentropic leve Mb iii EE a EEEE O OAA AA AAAS AEAEE EE EEE E ii 40 O27 WANG MON E E E A A A A A 40 9 7 1 Wind analysis Choices cocaina dd 40 9 8 Precipitation Menu ada 40 9 821 Precipita O ie 40 QQ SO a MMO MU esos seca A A Seca sae nsdn vn dos out os Vedas a E 40 9 91 Brief i MtrOGUCtiOn iii A aissdecsinahiedessidduvevatevedecacevactal 40 9 9 2 Sea Surface temperature conmmmnniccccnncnnnnnnsr rr 40 Ce e e A A RS 41 A A A ETT E E T 41 9 9 5 DIr Cti OM sevssissnvsvevesiasseccseccveceseasvedes cnusdnststucusususususcusvsusuduchsuchcudees ds sls sldsslst ssduvusudvdudvdedudududududedsiddsdedededsueddddn 41 CI O O TT 42 910 13D MAA abs 42 9 10 2 ROAMING SOUNCING sssini neee aaaeeeaa e ee aa eaaa aa a aa aa aeaa a a a e aaaea aa anean 43 910 3 Cross SBO eerren anaana aN EEE r a a r Eaa aa EEEE PEPEPEPE PEPEE pE RAR 43 911 MVFR IFR Weather aa cic fe ee a aap a a aaa aa aaa ld 43 9 12 Custom data field ii idad 43 93 ood E aa E a ET 43 9 14 Wind Feli id 43 9 15 GEOSEOp TIC WIN iso eee cers cece cee cca vee a ce eae aches ae est 43 9 16 Ageostrophle Wind acts sats inas abe ea aus Sha Sedan ct asea daaa tema pedicel eaaa lad ctel eked 44 OTT E LA o ai Bese seca ihes cee eas ace A T 44 9 18 Flow MOGITICHS 225 022 E EE EE E eed ovens d
9. Shipping Orders sales weathergraphics com Tech Support Product Information support weathergraphics com World Wide Web www weathergraphics com Page 1 Digital Atmosphere 2 Page 2 Introduction and legal notice by Tim Vasquez software author Norman Oklahoma Thanks for trying out Digital Atmosphere This software initially developed in 1992 and rewritten under Windows in 1996 encompasses thousands of hours of programming by one person me and is the unique result of over fifteen years of forecasting experience working with various meteorological workstations and mainframes and many years of amateur observation activities and storm chasing This manual is designed to help you get up and running with this advanced but easy to use weather analysis program It will start out by taking you on a short overview of Digital Atmosphere Following that each menu command is explained in detail Finally there is an extensive appendix with possibly all the miscellaneous information you could ever want If you acquired a lite version of Digital Atmosphere certain features will not work and you will need to register in order to get these capabilities The philosophy is to give users basic plotting capabilities in the lite version and bundle all the extras and freebies in the full version Information on how to register are in the next section WHAT IS DIGITAL ATMOSPHERE It s a powerful weather prediction tool It
10. want to look view data from several files at the same time Digital Atmosphere 6 6 6 7 If you use the Internet you can avoid all use of Import by using Internet Retrieve Data Digital Atmosphere will get data from the Internet and import it automatically when it s finished If you need more detailed information consult the Appendix for technical information on data import WARNING Never import a directory containing binary files programs or over 100 files The results may be unpredictable Clear data directory This is a utility command that clears out the data subdirectory data under Digital Atmosphere Normally it does not need to be used unless suspicious plots or contours occur and the user wishes to flush out all data This ensures that File gt Import directory does not inadvertantly retrieve files that were placed there by the user It can also prepare the data directory in case the user wishes to place numerous files into the directory to be imported Data that has already been imported and stored in native binary format will remain unaffected but Import directory will not work at all until new data is placed in the data directory via a file copy or via the Internet gt Retrieve command Get archived data If you have the Surface Archives or Upper Archives disc sets from Weather Graphics Technologies you can use this option to retrieve data on the disc instantly Digital Atmosphere will decompre
11. Configuration Se x Scripts are specified by a four digit execution time a space and the filename of the script For more information see the help files 0015 example dsf 0615 c wx other miscl dsf 1215 example dsf 1815 c wx other miscZ dsf i J Enable timer al Tae VALID SCRIPT COMMANDS SET keywordnumber keyword Sets a specified keyword 1 through 9 to a certain value You can then use this keyword later on in the same script simply by placing the token x anywhere in the code where x is the keywordnumber This is useful for managing large scripts Example SET 1 500 Sets keyword 1 to 500 PRODUCT 1 HGT 1 indicates 500 so here 500 mb heights are plotted PRODUCT 1 TMP 1 indicates 500 so here 500 mb temperatures are plotted TIMERON Enables the script timer It will adhere to the current timer script schedule TIMEROFF Turns off the script timer SLEEP seconds Causes Digital Atmosphere to pause for the specified number of seconds An hourglass cursor will be displayed during this time PRODUCT type level title Overlays a meteorological product on the map The appropriate data must have already been imported Valid type parameters are documented at the end of this section Levels are specified as follows for surface data the level is 0 zero for millibar levels the level equals the millibar level 500 etc and for FT height levels the level equals the ten thousands and thousands di
12. Its default setting is the Weathernode default of c weather wxdata rxfiles and should not be changed unless EMWIN data is stored elsewhere on your system Page 53 Digital Atmosphere 15 2 4 Page 54 Archives and imagewrites This is the directory where all output data automatic archives and imagewrites are stored Its default setting is digitalatmospheredirectory archive and may be freely changed as long as it corresponds to an existing directory and filename Files Files EMAIN surface datafile sahourly tt l EMVVIN RCM datafile saorcmus txt Imagewrite file output ipg Files EM WIN Surface Data The EMWIN system stores all surface data in sahourly txt but it is always possible at some point in the future this may be changed This option allows you to change the filename Ignore this if you do not have an EMWIN system Files EMWIN RCM Data The EMWIN system stores all RCM radar data in sarcmus txt but it is always possible at some point in the future this may be changed This option allows you to change the filename Ignore this if you do not have an EMWIN system Files Imagewrite file The EMWIN system stores all imagewrites automatically saved images when in scheduler mode to this filename If you choose autoname imagewrites under Scheduler this entry will only be used to determine what type of graphic file to write Digital Atmosphere 15 2 5 Scheduler Scheduler
13. JPEG image compression Large filesize p Small filesize Good quality Poor quality 20 If you choose Map Export and choose JPEG as an image type the image will be compressed according to the settings you specify here JPEG is a lossy compression scheme which means that higher compression values result in degradation of the image As the user you select the tradeoff that you think is most acceptable For a typical 640 x 480 image a setting of 0 loose will result in a high quality image with a filesize of 225K A setting of 100 tight will result in a very coarse image with a filesize of 11K Lat Long Grid cLatlong grid C Line C Mixed C Cross C Dash Dotted Digital Atmosphere can overlay a latitude longitude grid and here you can control how it will be displayed You will see the lat long grids only if the lat long grids setting in the map element table is checked and only when you re generate a new map Note that the grid interval is controlled by the grid interval setting and the color is controlled by the grid color listed in the map element settings color table Line Plots latitude longitude as a series of lines Mixed Same as line above but also adds dots for every integer degree of latitude and longitude The size and interval of the dots is fixed and cannot be controlled Cross Plots a cross at each latitude longitude intersection Dash Plots latitude longitude as a series of dashed lines
14. Page 63 Digital Atmosphere Page 64 Plot model configuration A grid of combo boxes are set up in a way that represents the various data positions around a given station plot You can use these combo boxes to adjust the kinds of data that are plotted in the different positions A Save Plot Model and a Load Plot Model option are provided so that you can make quick on the fly changes to the desired plot model Load plot model Loads a predefined plot model configuration from disk Save plot model Saves the current plot model configuration to disk Valid plot elements Units marked C or F or ft or m or sm or m are in metric or English according to File gt Preferences gt Meteorological gt Units unless otherwise specified here blank Nothing will be plotted in this space TEMP Air temperature in whole degrees C or F TEMP 10 Air temperature in tenths C or F DWPT Dewpoint in whole degrees C or F DWPT 10 Dewpoint in tenths C or F GUST Wind gust kt RH Relative humidity MXR Mixing ratio g kg THETA Potential temperature deg K THETAE Equivalent potential temperature theta e deg K WINDCHILL Wind chill HEATINDEX Heat index SLP Sea level pressure mb plots tens units and tenths ALSTG Altimeter setting in Hg plots units tenths and hundredths WX Pictogram of current weather type VIS Prevailing visibility sm or m ELEV Elevation ft or m CIG Ceiling lowest layer occupying
15. Plots the precipitation total as obtained from the 6xxxx group of SYNOP reports and the precipitation group of METAR reports Sea menu Brief introduction Sea data is provided by WMO FM 13 format ship synoptic observations These are usually carried in any data source that provides synoptic observations Sea data is not provided in METAR upper air or other formats Sea surface temperature Analyzes the sea surface temperature using units specified in File gt Preferences gt Meteorological gt Units Digital Atmosphere 9 9 3 9 9 4 9 9 5 Height All units for heights are in units specified in File gt Preferences gt Meteorological gt Units Wind wave Height of wind waves This is usually the best choice for an overall look at oceanographic conditions Primary swell Height of primary swell waves Secondary swell Height of secondary swell waves Instrument Height of waves obtained by instrumental methods Period Wind wave Period of wind waves This is usually the best choice for an overall look at oceanographic conditions Primary swell Period of primary swell waves Secondary swell Period of secondary swell waves Instrument Period of waves obtained by instrumental methods Direction Although swell direction vectors equal the direction from which the waves are originating they are also given an arbitrary magnitude that is equivalent to the wind wave height This helps give added empha
16. TTPTTRIR2R3 VVVLI PSDDFF HHT1T3T5 SEA 928157 03005 131714 30989795 GEG 894554 03407 152312 25969490 06021947750 05304 021921 34009996 06000877354 02207 101416 29979693 12010957438 1802 992315 30019995 12014928044 03104 021809 32999795 18006957340 01501 992612 30019995 18000957342 02502 012208 30999895 24005977941 02601 012517 28019995 24011957646 02502 022516 29999794 30010967941 01201 042819 27019894 30000957544 01001 042513 27009894 36005856037 0202 102814 26019894 36004938141 01501 072607 27009794 42000794430 0906 152811 25019793 42003837138 00703 123009 26009693 48000783339 0510 182710 27009792 48000614637 00007 173109 24999491 OP NY Version change summaries VERSION 2000 V1 0a maintenance 4 16 01 e Added mixed grid option in Preferences gt Maps e Adds revised station tables VERSION 2000 V1 0a 1 20 01 e Eliminates problem reported in V1 0 with left third of screen occasionally being blotted out at random Digital Atmosphere Analysis gt Export Last Analysis has been removed and in its place the text output is always written to GRID TXT Added SLEEP command to Scripting see Appendix Scripting section Corrected program so that a timer script will only execute ONCE per scheduled time interval The previous version would keep re executing the script as long as the current time was the scheduled execution time Added rule file DIGATMOS RUL with rules for importing observations
17. Worth Weather Products Electronic Service Solutions 3821 Del Rio Drive Ft Worth TX 76133 817 292 6579 888 837 2831 817 292 8836 fax http www ftwtexas com ftwp Sells Maryland Radio Center WeatherNode packages demodulators computer equipment rebuilt laptops for field use VHF receiving and transmitting equipment Page 91 Digital Atmosphere Weather Warning Systems 1213 James St Buffalo MO 65622 417 345 2917 http www jtronics com Offers software demodulators radio equipment GOES satellite equipment and retransmission transmitter and equipment Tigertronics 400 Daily Lane P O Box 5210 Grants Pass Oregon 97527 541 474 6700 541 474 6703 fax http www tigertronics com Sells EMWIN modulators and demodulators 1200 2400 and 9600 baud Affinity Computer 197 North 20th St Battle Creek MI 49015 616 962 3740 616 962 3711 fax http www battle creek com affinity Sells EMWIN equipment More details The National Weather Service coordinator for the EMWIN project is Kenneth Bashford NWS EMWIN Project Coordinator National Weather Service W OSO13 1325 East West Highway SSMC2 16358 Silver Spring Maryland 20910 301 713 0386 x191 Kenneth Bashford Onoaa gov Full details about EMWIN can be found at this web site http www nws noaa gov oso oso1 oso12 document emwin htm EMWIN Rebroadcast Frequency List Individuals should only be called for site information not for general technica
18. air or the relative rate of increase of a material surface Divergence is defined by the following where u and v are the x and y components of wind respectively Digital Atmosphere 9 19 Relative Vorticity Relative vorticity is a measure of curl of the air Geometrically vorticity is twice the angular speed of rotation of a parcel that moves with the flow It is a relatively simple expression of the flow of air and is most often used to examine the wind field within the boundary layer Relative vorticity is defined by the following where u and v are the x and y components of wind respectively Absolute Vorticity Absolute vorticity is the same as relative vorticity however the Coriolis effect is added into the equation absolute vorticity equals relative vorticity at the Equator Absolute vorticity of the wind is used most frequently in upper air analysis Advection When this item is checked Digital Atmosphere will use the results of the next analysis together with the flow modifier to calculate advection All computations of advection including Q vectors are based off of the real wind Advection measures the transport of an atmospheric property such as temperature or precipitation by the wind Isentropic analysis This section has not been completed Page 45 Digital Atmosphere 10 10 1 10 2 Page 46 Internet Menu Commands Introduction Before you use any of these commands you will need to
19. amateur radio gear Digitronics Inc P O Box 937 Round Rock TX 78680 0937 512 255 0664 Sells software demodulators radios Ku and GOES satellite equipment Weather Affirmation L LC P O Box 13057 Oklahoma City OK 73113 1057 405 478 3590 Sells software demodulators radios GOES satellite equipment alphanumeric paging service and equipment W A T C H Weather At The Current Hour P O Box 16861 10501 East 63rd Street Raytown MO 64133 0961 816 356 5151 http members aol com kcwx watch html Offers Maryland Radio Center WeatherNode software and demodulator GOES Satellite Receiving System and WeatherNode Software and radio receivers DuMond R C Service Company 2626 Valley View Suite 4 Farmers Branch TX 75234 near Dallas 972 241 8492 http www weathernode com dumond index htm Carries software demodulators radios R C service and is the national distributor for WeatherNode resellers OnFireVB Software 714 831 5324 http www weathernode com onfirevb index htm Offers software to add faxing and paging capabilities to WeatherNode WeatherTech Systems 412 Wooded Trail Longview TX 75605 903 663 4939 http www tornadowarning com Weather Technologies 2812 North 9th Str Canon City CO 81212 719 275 0485 Sister companies that offer the Maryland Radio Center WeatherNode Software demodulator GOES satellite downlink equipment retransmission equipment and weather station equipment wireless Ft
20. amount of basic weather data and bulletins free of cost without tying up a phone line We recommend that all amateurs look into this method of receiving data For value added products such as radar imagery detailed upper level data and so forth EMWIN will be of little help and you will need to set up a separate dial up or Internet account with a commercial data provider What it offers The EMWIN system contains many categories of weather data products with over 6 500 unique products Altogether your PC will have about 5 megs of weather data at any given time The current EMWIN datastream contains all generally available public products from the NWS Telecommunications Gateway including the following product categories Analyses Environmental Air Pollution Hydrological Marine Surface etc Climatic Products Daily Surface Monthly Surface etc Forecasts Aerodrome Aviation Area Extended Flash Flood Guidance Headwater Guidance Hydrological Iceberg Local Area Public Recreation Travelers River Shipping Area etc Graphics AFOS charts and map overlays Images GOES satellite Misc Civil Emergency Messages Public Weather Statements Reports Radar Seismic Synoptic Hydrological River Drifting Buoy Ice Severe Weather Warnings Summaries Statements Advisories Warnings Tsunami Tide Tornado River Flood Lakeshore Marine Typhoon Hurricane Marine Coastal Flood Severe Thunderstorm There are also graphics which include
21. and can only be modified using the File Quality Control function Importing The process of crunching raw data This is how you feed new data into Digital Atmosphere The data is stored in formatted data files Isoplething The process of Digital Atmosphere drawing contours or lines on the screen as the result of an objective analysis Isopleths are not plotted they are drawn Map attribute file A small file 36 bytes that is paired with a geographical bitmap file to provide mathematical mapping information about that image A map attribute file has the file extension ATR Map generation Forcing Digital Atmosphere to draw a customized map based on latitude longitude and zoom settings that the user selects Objective analysis The process that Digital Atmosphere undergoes before it can show a contour or isopleth It consists of looking at data at randomly spaced points mapping it to a grid and running smoothers on the grid In the context of this user s guide I will refer to objective analysis as simply analysis and refer to human analysis as hand analysis etc Ocean fill The blue color that Digital Atmosphere usually draws in oceans and lakes Plot See station plot Primary field An atmospheric property that the user chooses to analyze The user may also force Digital Atmosphere to calculate a derivative field of the primary field Page 79 Digital Atmosphere 17 2 Page 80 Raw data file The ori
22. arising from the use misuse or attempted use of this product including injury death and or loss of earnings Users who require a significant degree of forecasting accuracy shall use other tools in conjunction with Digital Atmosphere and shall seek the assistance of qualified meteorological consultants The author reserves the right to make changes and improvements to Digital Atmosphere to the User s Guide and to sales and pricing policies at any time and without obligation to notify any person or organization of the revision or change All brand and product names are the trademarks of their respective owners Microsoft and Windows are either trademarks or registered trademarks of Microsoft Corporation Digital Atmosphere is a trademark of Weather Graphics Technologies Page 3 Digital Atmosphere 3 Page 4 Why register Where How much WHY REGISTER Your Digital Atmosphere 2000 copy is a fully functional version There are no separate registered and demo versions and there s nothing else to download or install However you must register Digital Atmosphere 2000 within 30 days If you don t do this at the 30 day point the software will disable certain features such as quality control photorealistic maps scripting climatology and loading saving of maps When you register you will receive a key number that you enter into Digital Atmosphere This prevents it from expiring and restores expired copies What other ext
23. at and analyze the data at this level Commonly chosen analysis options for isentropic analysis are Isentropic Height mb Wind Field and Relative Humidity The basic premise of isentropic analysis is that air moves three dimensionally and it does NOT stay confined at constant pressure levels As expressed by isentropic advocate Dr James Moore Pressure coordinates bad Isentropic coordinates good Constant pressure coordinates have been used for decades because of their simplicity but computational power now allows forecasters to become familiar with isentropic coordinates Most airflow moves along isentropic surfaces surfaces of constant potential temperature which are shaped according to large scale thermal structures By using isentropic maps we can assume upward motion is occurring wherever wind is blowing air from higher to lower pressure levels lower to higher altitudes Since isentropic analysis is based on adiabatic assumptions it will not work reliably where air is saturated in convective situations or near the ground It will also not work well when a weather system is moving rapidly For more information see http www eas slu edu People JTMoore isenbasics index htm Override level This is simply a way to roll your own heights to analyze rather than being forced to use standard levels like 500 mb 300 mb etc The Override 3 D option is chosen under Level on the speed toolbar When an analysis is chosen you will be aske
24. choice of units in File Preferences At the bottom you ll see average monthly precipitation totals United States or precipitation days elsewhere The total height of a precipitation day bar is the total precipitation days during a given month The part in gray is how many of those days are composed of snow days and the part in red is how many are composed of thunderstorm days Introduction Digital Atmosphere maintains a database of numerous monthly weather parameters for over 2 000 weather stations across the world Most of this archive spans a 30 year time period This data can be viewed on a graph or plotted on your maps Keep in mind that as with most other meteorological data the results may be affected by the observing station s elevation or proximity to the ocean This is why you may see significant variations in temperature along a coastal region among other effects Page 49 Digital Atmosphere 13 13 1 13 2 Page 50 Window Commands Add remove toolbars You can add or remove toolbars as needed to make more space on your workchart Remove last product Removes the last data overlay from the screen Digital Atmosphere 14 14 1 Help Commands Register t Register A ES Serial number oa3 3400 1 41623296 Key number que The Help gt Register dialog allows a user to unlock an unregistered version of Digital Atmosphere It usually only needs to be done once The trial version will
25. cloud cover being indiscernable for reasons other than fog or other meteorological phenomena or observation is not made Synoptic cloud height codes CLDHGT h h is reserved for the height of the surface of the base of the lowest cloud seen They are as follows below If the total sky cover is greater than 4 8ths this figure is also transposed into the CIG slot where they are plotted as L low cloud followed by a loose translation of the table below in hundreds of feet This L differentiates it from true ceilings where C E or M is prefixed 0 0 to 50 m 1 50 to 100 m 2 100 to 200 m 3 200 to 300 m 4 300 to 600 m 5 600 to 1000 m 6 1000 to 1500 m 7 1500 to 2000 m 8 2000 to 2500 m 9 2500 m or more or no clouds Height of base of cloud not known or base of clouds at a level lower and tops at a level higher than that of the station Upper air plot model UPPER PLOT MODEL IV Plot wind barb IV Fill dewpoint depression circle TEMP C v HEIGHT v eian hd DADEP C v eian Y Load Save These settings only apply when the active level is an upper level and Overlay Data is selected e Plot wind barb If checked Digital Atmosphere will plot a wind barb at each station plot when it is reporting valid wind data If unchecked no wind barb is plotted on any report e Fill dewpoint depression circle If checked Digital Atmosphere will shade in the station plot of each upper level s
26. filename Uploads a product to an Internet source The url is the fully qualified RFC 1738 standard URL including filename and filename is the full local name of the file to be uploaded Example upload ftp userid password ftp mydomain com anonftp pub out jpg c da20 bin map out jpg ARCHIVE cddriveletter yymm yymmddhh Accesses data from the Weather Graphics Technologies Surface Archives or Upper Archives CD ROM The cddriveletter parameter is the drive letter while yymm is the year and month full four digits and yymmddhh is the year month date and hour full eight digits LOAD filename Loads a map The filename parameter is the fully qualified filename without the extension i e without bmp SAVE filename Saves a map The filename parameter is the fully qualified filename without the extension i e without bmp EXPORT filename Exports a map i e saves it to a variety of formats and without the accompanying atr file The filename parameter is the fully qualified filename with a valid extension may be bmp gif jpg png pcx or tif Compressed TIFF saving is not available GRADIENT on off Turns on or turns off the File gt Preferences gt Contours gt Gradient Fill option GRADIENTCOLOR red blue green ph1 ph2 scale offset value Sets one of the File gt Preferences gt Misc gt Gradient Color settings to a particular value This allows the script to change a contour gradient scheme on the fly SFCPLO
27. for default time selection It s assumed that most people will only want to use Show Contents First in special cases A Data Check interval has been added in Preferences in the General tab In earlier versions Digital Atmosphere checked for new data every 20 seconds This is now user specifiable During find operations in View Raw Data the cursor is now an hourglass New station tables are now packaged with the upgrade This consists of DIGATMOS RIX DIGATMOS STI DIGATMOS STW DIGATMOS SXI and DIGATMOS SXW This fixes some persistent range check errors with surface data that were present in the beta version The Internet alphanumeric product retrival list DIGATMOS SLZ has been updated slightly Soundings have been reinstated The sounding window contains a box where you can enter the desired station and easily view consecutive stations Background maps now plot after a gradient analysis You can now overlay the base map without erasing the graphics thanks to the new Map command Add basemap The status bar at the bottom of the screen has been restructured It now holds a progress bar detailing all ongoing operations the task progress and the ingest mode currently in use Additional status notifications have been added throughout the analysis module and other processes CHANGES FOR V2 1B BETA to V2 1C BETA FEBRUARY 1999 Isentropic analysis has been reinstated The isentropic level can be selected from the Statu
28. free air temperature and the relative humidity Relative humidity This is a measure of how close the air is to being saturated An analogy is having a shot glass half full of water and a large jar half full of water Relative humidity is like saying that each of the containers is 50 saturated with water regardless of the true amount in the container Mixing ratio This measure tells you exactly how much moisture is in the air It is calibrated in grams of water vapor per kilogram of air Mixing ratio is basically the same type of measurement as dewpoint however mixing ratio is an absolute measurable quantity and with increasing amounts of moisture changes in mixing ratio become more significant than changes in dewpoint This makes it ideal for finding features in moist air masses especially in severe weather situations At the surface by checking the divergence derivative and clicking mixing ratio you can produce a moisture convergence chart useful for forecasting severe thunderstorms By clicking that and the advection derivative you can produce moisture flux convergence SMC In an unstable atmosphere it takes a few hours for Digital Atmosphere 9 5 5 9 5 6 9 6 9 6 1 9 6 2 9 6 3 9 6 4 SMC to produce convection so persistant SMC areas must be watched SMC patterns are more important than the actual values Dewpoint temperature The dewpoint is the temperature that the air must be cooled to
29. how many to ignore Station plot density This slider bar is only enabled when Plot All Stations is unchecked By adjusting the position of this slider bar you can change the density clutter of station plots whenever you choose Overlay Data or Overlay Custom Data Analysis Analysis tab Also see the special topics on Analysis type and Analysis parameters Page 67 Digital Atmosphere Page 68 TT Thick contour lines Figure geostrophic heights height contours will take longer to draw V Perform isopleth Automatic smoothing I Perform gradient fill Show gridpoint values Thick contour lines If checked this gives all contour lines a width of 2 instead of 1 Show gridpoint values If checked scalar field values are plotted at each analysis gridpoint This is used mainly for diagnostic purposes This should normally be left in the unchecked position Perform isopleth If checked scalar fields are drawn using isopleths lines connecting equal values This is the normal setting and should normally be left checked Perform gradient fill If checked and a scalar analysis is selected the entire screen is painted in hot or cold shades depending on whether the analysis value is high or low respectively You cannot modify the colors that are painted and you should use plain maps without topography for best results It is advised to leave both Perform Isopleth and Show Gridpoint Values unchecked if you se
30. is suspected A box will appear as shown below Hie IDs 76_ 05 ____ BBQNE I 750 ESB When you select File gt Quality Control or press the QC speed button the quality control panel will appear as seen below Digital Atmosphere t Quality Control Panel iof x Temperature deg ICAO kama Dewpoint deg C AMO F ind direction deg true LAT fps23 0 ind speed kts E 01 72 ind gust kts EN Sky cover oktas ELEV f 093 Ceiling feet 00 TIME f 153 Ceiling method code MB LEVEL sss Weather pains Rey cee FTLever osas Visibility weord text Visibility value meters Altimeter setting in x 100 Sea Lvl Pressure mb Ignore changes Pressure tendency mb x 10 no negs Pressure trend a code 0 to 8 x ESOPO Precip amount mm Precip amount period hr 9998 dry A iia Cloud codes L M H asas asas Help You may then edit the values shown and correct any entries that look suspicious Always use a value of 9999 to indicate missing data Note that the data shown is dependent on what the active level is as is shown on the Time Toolbar If the active level is a non surface level Quality Control will only display upper air data If the active level is a surface level Quality Control will display only surface data The options you have are e Accept Entry Saves the report as shown including any modifications you might have made Once you hit Accept Entry all changes become
31. mailing address info that we have on file so that we can verify your status If we cannot find this you will need to submit clear proof of purchase credit card statement receipt etc e Individuals who purchased Digital Atmosphere after April 1 2000 You are grandfathered to this edition for free You will need to specify in your order that you registered after April 1 2000 we will check this with our records and you will need to provide your mailing address info that we have on file so that we can verify your status If you want the CD ROM a 10 charge will still apply e Texas residents We re Texas based and the 8 25 tax rate applies to all individuals in Texas WHAT YOU GET WHEN YOU REGISTER All users will receive a key number that will allow the program to be unlocked There s nothing else to install or download This key number will keep your copy fully functional without the headache of it expiring Digital Atmosphere DO I NEED THE CD ROM VERSION For many users the answer is no you don t need the CD ROM version You should only order the CD ROM version if you want the Operational Mesoanalysis PDF document if you don t want to download the program or if you want to have a readily available backup copy of Digital Atmosphere The downloadable version and the CD ROM version are exactly identical in other words ordering the CD ROM doesn t give you a different version of Digital Atmosphere It s strictly provided
32. notify the author of any program segments where this setting is ignored Modifying the units for station plots is done in the Station Plots panel not here Page 57 Digital Atmosphere 15 3 3 Precipitation units Inches e Millimeters ne m Picks whether precipitation totals will be plotted contoured in units of millimeters mm or inches in FOUS data level FOUS data level e TURA sfc C T3R2 low level C TSIR3 mid level Whenever you plot model ETA NGM data the temperature and moisture variables are determined according to this setting Normally the first button T1 R1 is selected to give you surface data but by choosing another button you can plot or analyze temperature or moisture aloft calculating derived values such as dewpoirt should be done with caution though since T3 is not the same level as R2 Here are the meanings of the different levels Level Equivalent TI Surface T3 About 100 mb above the surface 1 km TS About 215 mb above the surface 2 km R1 Surface to about 35 mb above the surface lowest 1000 ft R2 About 35 mb above the surface to 500 mb R3 500 mb to the tropopause 15 3 4 Parcel lift calculations Page 58 Parcel lift calculations C Surface based parcel Lowest 100 mb C Lowest 150 mb C Best layer Parcel lift calculations This setting is consulted by the analysis module when CAPE and other instability parameters a
33. old format without converting them to the new format Various stations have also been added worldwide There are no longer overflow problems with the View Raw Data window Imported data greater than 64K in size used to generate a text exceeds memo capacity error when the user viewed it through File View Raw Data The viewer has been replaced with a new 32 bit component which does away with the error Sporadic range check errors during data imports have been eliminated The error was caused when erratic WMO numbers in synoptic data were looked up in a station table An import is automatically done after retrieving Internet data This eliminates an extra step that the user had to do in the past It is now impossible for a station plot to appear at the intersection of the equator and the prime meridian Occasionally when a report can t be processed correctly Digital Atmosphere is forced to assume it has a latitude and longitude of zero You can now adjust the lowest possible METAR pressure under the Preferences Meteorological tab to change how the hundreds place of a coded METAR sea level pressure is determined This is useful when contouring very low or very high pressure Page 107 Digital Atmosphere Model output thicknesses between 4800 m and 4999 m are now handled correctly Since they are coded as hundreds and tens earlier Digital Atmosphere versions simply assumed the thousands place was 5 You can now specify to cr
34. s hands down the leading weather software program for Windows and is used by the National Weather Service the Air Force and Navy dozens of television stations and consulting firms and hundreds of amateurs and hobbyists Its powerful and rapidly expanding capabilities will let you monitor developing weather anywhere on Earth around the globe or right in your own local area Digital Atmosphere is essentially a geographical display program that ingests raw weather bulletins disseminated by the National Weather Service to Internet sites satellite feeds and weather databases Using this data it produces stunning plots and analyses that are equivalent to those found on multi million dollar workstations The maps and other products you create with Digital Atmosphere are fully customizable You can define the geographic area you wish to map and specify the map s resolution You decide how much detail you want shown in your maps from country borders only to rendered topography with county lines and roads overlaid You choose what weather data you want displayed how the data is displayed and in many cases what algorithms are used to analyze the data Whatever your meteorological graphics needs Digital Atmosphere can create exactly the map you desire using only the parameters you desire DIGITAL ATMOSPHERE IMPORT SPECIFICATIONS e Land synoptic WMO FM 12 SYNOP e Ship synoptic WMO FM 13 SHIP e METAR WMO FM 15 METAR e Buoy WMO FM 18 B
35. second column is the WMO station identifier for SYNOP data The third column is the name of the station city as it should appear on your weather map KORD 72530 Chicago KSEA 72793 Seattle KSFO 72494 San Francisco KLAX 72295 Los Angeles KBOI 72681 Boise KABO 72365 Albuquerque The font used by this plot type is specified in File gt Preferences gt Fonts Warnings Plots warnings that were imported from the most recent data import Frontal depiction ASUS1 This option allows plotting of georeferenced fronts highs and lows The features are georeferenced therefore you can always plot them later even if you zoom in or quit the program You will lose your frontal depictions if you again create a depiction or if you import original ASUS1 data Plot Displays whatever frontal bulletin currently resides in the QUEUE FRT file This bulletin may be imported from the Internet see using original sources of data below or may be created by the user see create and making your own maps below Create Allows the user to create fronts highs and lows from scratch using rudimentary drawing commands see below Append Allows the user to append fronts highs and lows to a frontal bulletin currently residing in the QUEUE FRT file Page 31 Digital Atmosphere Page 32 Using original sources of data Raw sources of data consist only of the ASUS1 KWBC numerical text bulletin produced by the National Weather Service Th
36. settings If you use a proxy host enter the name and port here If you do not know the proxy settings you will need to contact your ISP Our tech support personnel cannot guess these settings or Page 75 Digital Atmosphere look them up for you For example users of Alphalink in Melbourne Australia will notice on their Alphalink support pages that they would need to enter proxy alphalink com au in Proxy host and 8080 in Proxy port Photorealistic topography This preference setting is only used in the full blown version e Smooth final image Applies a smoothing function to the photoreal map e Reoverlay geography Plots the basemap on top of the photoreal map Checked by default Color gradient fills This section lets you define how gradient fills will look It is designed mostly for experienced users and will require some basic mathematical knowledge The colors are defined according to the plotted Value for the particular point on the map which will always be in the range 0 1 where 0 is the lowest possible reading and 1 is the highest possible reading This Value is fitted to a sine wave according to user defined parameters to determine the Red Green and Blue component of its color First the value 0 for minimum possible and 1 for maximum possible is fitted to the sine wave to determine what the amplitude will be Amplitude will always be in the range 1 to 1 Amplitude is determined by ph1 and ph2 which are in degrees A grea
37. stills of hurricanes and tornadoes scanned charts of weather symbols and tutorials weather screen examples found on the Internet and so forth Surface METAR data for the entire United States is transmitted hourly for which Digital Atmosphere 2 0 is already adapted and there are plans to broadcast upper level rawinsonde data shortly When this occurs a Digital Atmosphere patch will be released to help accommodate it Transmission of raw data for broad international regions is being planned OPTION 1 OF 2 Satellite based reception Satellite broadcast is the main method used for disseminating the EMWIN datastream The data originates from the National Weather Service is uplinked from Wallops Island Virginia and you receive it with your satellite dish This allows hemispheric coverage using the GOES 8 and GOES 9 weather satellites GOES 8 is geostationary at subpoint 75 deg W and GOES 9 is at 135 deg W Page 89 Digital Atmosphere Page 90 THE SCOOP The 9600 baud signal transmits at 1690 725 MHz converting to 137 225 MHz while the weaker 1200 baud signal transmits at 1690 6 MHz converting to 137 1 MHz The EMWIN data is also currently uplinked to the Galaxy 4 satellite by Spacecom Systems of Tulsa OK as a public service at 99 deg W Ku band Transponder 4 FM FM DFSK 0 5425 MHz subcarrier Due to the success of the 9600 baud transmission which is already being received successfully on small 3 foot dishes the 1200 bau
38. surface when viewing surface data Set it to a mb level when viewing rawinsonde data Set it to a ft level when viewing FD winds aloft or RCM wind data R Press this to delete all of the ft entries from the level list except those used for RCM wind data F Press this to delete all of the ft entries from the level list except those used for FD winds aloft data All Press this to restore all ft levels including FD and RCM wind data Analysis toolbar Wind Controls what type of wind information is used during any Analysis operation Leave this on observed for most typical uses Otherwise choose geostrophic ageostrophic or Q vector to view these respective wind fields Wind plot Controls what symbology is used to display wind fields during any Analysis operation You can choose from barbs or choose vectors Derived field Controls what kind of derivative field is used when producing any kind of Analysis You should leave this on No except when producing vorticity or convergence maps For more information on derived fields see the chapter on Analysis Advection box If checked an advected derivative field will be used during any kind of Analysis You should normally leave this unchecked Script toolbar The script toolbar is a powerful interface that lets you give Digital Atmosphere a certain degree of automation You can initiate tasks at various hours For more information on working with scripts ple
39. symbols are plotted at each radar location together with the radar echoes By unchecking this box only radar echoes will be plotted Surface plot model SURFACE PLOT MODEL IV Plot wind barb IV Color code IFRM VFR plots IV Filter ASOS reports Y Smart visibility plot kron y Psem y fue y foxtas 7 fpreno y Load plot model Save plot model These settings only apply when the active level is the surface level and Overlay Data is selected e Plot wind barb If checked Digital Atmosphere will plot a wind barb at each station plot when it is reporting valid wind data If unchecked no wind barb is plotted on any report Filter ASOS reports If checked Digital Atmosphere will plot human observations first with automated ASOS AMOS automated synoptic etc as last priority If unchecked no priority is assigned to any observation Smart visibility plot If checked Digital Atmosphere will omit plotting surface visibility when no significant weather is occurring If unchecked surface visibility is always plotted Color code IFR MVFR plots If checked when stations are reporting IFR conditions visibility less than 3 miles and or ceiling less than 1000 ft the OKTAS sky cover plot symbol is colored red when MVFR conditions visibility less than 5 miles and or ceiling less than 3000 ft the OKTAS sky cover plot symbol is colored blue If unchecked the standard draw color is used to paint the sky cover plot symbol
40. the map and then use a photo editing type graphics program such as Photo Shop or Paint Shop Pro to make a negative image or enhancements that allow for better printouts If the printer shows memory errors this means that the graphic you are sending to the printer is too large to fit into the printer s memory The easiest way to remedy this is to go to File Print Setup and choose a portrait printout rather than a landscape printout Another solution is to regenerate your charts without using any color fills or topography i e totally composed of line graphics The third method of solving a memory problem is to use a lower resolution i e choose 600 dpi rather than 1200 dpi or 300 dpi rather than 600 dpi in your printer setup The final and best solution is to increase the amount of RAM in your printer by installing a SIMM memory module Your printer will require a total minimum amount of 2 MB of RAM but will work best with 4 MB or more Some users report problems printing to HP LaserJet and a couple of other printers such as getting blank pages This is usually a problem with the Windows PCL 5 print driver and is beyond the control of Digital Atmosphere Solutions for this that have been documented are changing the resolution from 600 to 300 dpi or change the print mode from vector to raster If your printer is equipped with a PostScript option always use the PostScript mode for 600 dpi printing Overall this printing problem is not specif
41. to the public It is somewhat more commonly available than sea level pressure so it finds use in day to day mesoscale analysis Sea level pressure The sea level pressure is the atmospheric pressure at the surface in millibars reduced to sea level taking into account temperature patterns over the previous 12 hours It is similar to altimeter setting but not the same Its biggest use is for comparing patterns over a broad area as in synoptic analysis Page 39 Digital Atmosphere 9 6 5 9 7 9 7 1 9 8 9 8 1 9 9 9 9 1 9 9 2 Page 40 Isentropic level mb If a 3 D analysis has been created and the active level is Isentropic 3 D this option will allow the user to map out the height of an isentropic surface in millibars Wind menu Wind analysis choices Wind field Plots a staggered 31 x 31 grid of wind barbs or vectors depending on the setting on the Analysis Toolbar Barbs are calibrated in knots while vectors are an arbitrary length that is proportional to speed Streamlines Plots streamlines for the wind field at the active level Streamlines are lines always drawn parallel with the wind flow They are a function of wind direction and not velocity however they are not drawn through regions where the analyzed wind speeds are 1 kt or less Wind speed This is the speed of the air movement usually measured in knots nautical miles per hour or 1 15 mph Precipitation menu Precipitation
42. will appear Nondiscrimination between ETA and NGM data during contour operations has been fixed Earlier versions did not discriminate between ETA and NGM data according to the status panel during contour operations Appropriate labelling is now applied to charts when a contour of model data is done The registration information box contained within the program for new users has been updated to reflect a new E mail address and minor changes in sales policies Default color preferences have been fine tuned to get rid of contour line colors that match the background CHANGES FOR V2 1A BETA to V2 1B BETA FEBRUARY 1999 The lat long grid interval can now be controlled This is done in Preferences Maps A range check error that occurs during analysis of rawinsonde data has been fixed The File Print option has been fixed The diagnostics window in the beta version has been disabled The inverse print option had to be deleted due to an inability to make it work successfully without considerable programming Many PostScript drivers allow you to force the printer to make negative printouts Wind feathers are reversed in the South Hemisphere to meet standard convention One note however in the Analyze Wind Grid section the routines have to make the feathers a uniform style so the center position of the background map is what determines the style rather than each gridpoint location The status panel now uses Automatic
43. 3 Digital Atmosphere 15 8 15 8 1 Page 74 Contours Contours tab oo Meteorological Maps Station Plots Analysis Fonts Contours Misc cove cwreun ve a E E ecos z ATTE degf 0 5 n sold tmpu Upper Temperature fdegt 0 2 n dash red dews Surface Dewpoint deg f 0 5 n dash green dew Upper Dewpoint deg f 0 2 n dash green lddps Surface Dewp Depress deg c 0 5 n dash green lddpu Upper Dewp Depress deg c 0 5 n dash green thta Potential Temperature deg k 0 2 n dash green thte JEquivalent Pot Temp Jdegk 0 2 n soid red rhum Relative Humidity percent 10 20 n dot green wehl find Chill degf 0 10 n dash blue x Any changes you make to the contour settings will always be saved as a default setting This tab is where changes are made to contours that are produced under the Analysis dropdown menu Code This is an internal code It cannot be modified Contour type Indicates the purpose of this contour It cannot be modified Unit Proper entries are as follows Do not mixmatch units or the program will ignore the setting and use a default unit Units marked with cannot be changed Temperature deg f deg c deg k Moisture ws sa RS Relative Humidity lt percent Horizontal Velocity knots mph m s Vertical Velocity ub s microbars per second Height s s a s a meters Pressure mb hpa kpa inches Precipitation Totals in
44. 30 92762 01611 03014 85444 01850 00521 70993 04159 30025 50559 etc Weather watches Also called SELS watches watch boxes or even WWUS9 KMKC This is an English bulletin produced by forecasters at the Storm Prediction Center formerly NSSFC the National Severe Storms Forecast Center WWUS9 KMKC 141239 EL7 KC WW 141239 52000 142000 ULLETIN IMMEDIATE BROADCAST REQUESTED EVERE THUNDERSTORM WATCH NUMBER 77 NATIONAL WEATHER SERVICE KANSAS CITY MO 639 AM CST THU MAR 14 1996 A THE STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR PARTS OF EAST CENTRAL AND SOUTHEASTERN KANSAS U E S M K B S EFFECTIVE THIS THURSDAY MORNING AND AFTERNOON UNTIL 200 PM CST ARGE HAIL DANGEROUS LIGHTNING AND DAMAGING THUNDERSTORM WINDS ARE POSSIBLE IN THESE AREAS THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 45 STATUTE MILES NORTH AND SOUTH OF A LINE FROM 45 MILES WEST OF EMPORIA KANSAS TO 45 MILES EAST OF CHANUTE KANSAS Convective outlook The convective outlook is a bulletin produced by forecasters at the Storm Page 95 Digital Atmosphere 17 9 Page 96 Prediction Center formerly NSSFC the National Severe Storms Forecast
45. 5 521 2481 Digital Atmosphere 17 7 OK Ponca City 150 700 Tom Montgomery 405 763 8019 OK Poteau 150 750 Jim Conley 501 788 1833 OK Stillwater 148 775 Mike Veldman 405 744 8392 OK Tulsa 165 015 Jack Long 918 445 1488 OK Woodward 150 750 Suzanne Ellenberger 405 254 6728 SC Moncks Corner 141 500 Wes Blanchard 803 719 4167 TN Memphis 2 Steve Terry 901 725 8833 TX Austin 150 435 Larry Jentry 512 424 2208 2422 TX College Station 3 Lance Parr 409 775 7014 779 5367 TX Corpus Christi 150 435 Henry Wood South Texas Electric Coop TX Dallas 150 435 Fred Varian 214 464 6084 TX Houston 150 435 Jim Robinson 713 957 7498 TX LaFeria 150 435 Mike Partusch TX Longview 150 435 Jim Cox 903 663 4939 TX Port Lavaca 150 435 Billy Zwerschke EMC Calhoun County TX Temple 150 435 Gerald Moore 254 773 1101 TX Victoria 150 435 South Texas Electric Coop TX Burkburnett 150 435 Dave Spitler 940 569 4179 WY Cheyenne 141 300 Ward Noakes 307 777 4445 1 Off air due to interference 2 Broadcasts on 67 kHz subcarrier on 89 3 MHz Requires subcarrier SCA receiver 3 Broadcasts on 67 kHz subcarrier on 89 1 MHz Requires subcarrier SCA receiver About weather data Every day nearly ten thousand weather stations across the world disseminate weather observations These observations are taken according to standards and formats laid out by the World Meteorolog
46. AOB reports can t be deleted Users with slow computers will notice delays when plotting rawinsonde reports due to the large size of the upper air output file Since the code has been rewritten slightly there is a slight chance this fix could introduce errors so testers should note any plots or contours that don t seem to do anything Thanks to Phil Rider Rawinsonde data elements with solidii encoded anywhere in the element rather than just the first position are thrown out For example Katmandu was encoding heights like 5085 corrupting upper air contours Scalars temperature wind speed etc could not be contoured with FD data due to an unwanted line of test Page 101 Digital Atmosphere Page 102 code This has been removed Thanks to Phil Rider Various buoys such as those in the Arctic ocean omit the wind Oddff group confusing Digital Atmosphere and making it plot erroneous winds and sky condition This has been fixed EMWIN imagewrites were saving to the DA directory not the directory specified in Preferences Fixed Thanks to Jesse Ferrell Scheduled internet retrieval was not making its panel appear during retrieval this has been fixed Thanks to Wayne Cotterly Derived fields vorticity and convergence are now functional Radar status annotations now work with RCM data Thanks to Jesse Ferrell TVS signature will always be plotted in red Thanks to Jesse Ferrell A Preferences speed
47. America Africa Asia Australia and Antarctica where meteorological observatories tend to be bona fide weather offices rather than control towers or flight service stations Upper air data from balloon launches is taken worldwide twice a day It is transmitted in TEMP format also known as TTAA TTBB PPBB format and radiosonde format This format uses extensive numerical coding Availability of upper air data is fairly good across much of the northern hemisphere but is seriously lacking in the southern hemisphere where satellite based sensors are widely used to initialize computer model forecasts Since much of this data is freely available from a variety of sources Digital Atmosphere gives users a flexible tool for graphically importing and displaying all of the different weather data formats provided by the GTS Raw data samples Listed here are some examples of what kinds of data will be imported by Digital Atmosphere depending on your checkmarks on the status panel You can refer to these examples if you have any trouble getting Digital Atmosphere to read something or are unsure of what a particular product or bulletin should look like Airways SAO data This is the backbone of weather observation code in the United States and Canada It is issued hourly from thousands of weather stations A sample report will look like this JFK SA 1150 250 SCT 7 113 44 21 2513 989 SD RAREP radar reports Als
48. CAO of the station for display purposes only WMO xxx WMO number of the station for display purposes only LAT xxx Latitude in hundreds of degrees negative is southern hemisphere LON xxx Longitude in hundreds of degrees negative is western hemisphere LAX xxx Latitude in regular format negative is southern hemisphere LOX xxx Longitude in regular format negative is western hemisphere ELE xxx Elevation in meters used only for potential temperature calculations TIM xxx Time in UTC expressed as 450 for 4h50m and 1629 for 16h29m DAT xxx Day of month expressed as 16 for September 16 TMP xxx Temperature in degrees Celsius DWP xxx Dewpoint in degrees Celsius WND xxx Wind direction in degrees true WNS xxx Wind speed in knots WNM xxx Wind speed in meters second SKY xxx Total sky cover in oktas 9 obscured 10 not available CIG xxx Ceiling in hundreds of feet WXX xxx Weather code first and second digit equals ww weather code e g 61 is light rain VIS xxx Visibility in meters PCP xxx Precipitation total in millimeters PCT xxx Precipitation time period in hours PTR x Pressure trend equals a in app group PTN xxx Pressure tendency in tens of millibars SNO xxx Snow depth in centimeters CLL x Low cloud code CLM x Middle cloud code CLH x High cloud code MAX xxx Maximum temperature in degrees Celsius MIN xxx Minimum temperature in degrees Celsius Using exported analysis grids Whenever an Analysis is performed on
49. Center and intended for use by other National Weather Service meteorologists Two are produced one for the today time frame Day 1 and another for the tomorrow time frame Day 2 It is one of the best sources of forecast information on the potential for severe thunderstorms ACUS1 KMKC 141441 SWODY1 MKC AC 141441 CONVECTIVE OUTLOOK REF AFOS NMCGPH940 VALID 141500Z 1512002 REF WW NUMBER 0077 VALID TIL 20002 THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM PGO OKC 30 NNE P28 35 ESE SLN OJC JEF MVN EVV BWG BNA MEM PBF PGO GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM OXR FAT TPH ELY 15 NW PUC CAG LIC HLC FNB PIA FWA YNG DUJ DCA 25 W RIC RDU AND CBM W L5 TXK FSI 60 NNE AMA RTN 10 SE ABO 30 SS DMN Model output data These are numerical output bulletins from the National Center for Environmental Prediction NCEP formerly known as NMC which describe forecast parameters at different locations around the country These bulletins are available on most weather databases For those who want the real thing from the supercomputers full fledged model output is in a binary format known as GRIB these files ar huge hard to obtain and are not importable into Digital Atmosphere at this time 652 FOUS72 KWBC 201200 OUTPUT FROM ETA 12Z JAN 20 96 TTPTTRIR2R3 VVVLI PSDDFF HHT1T3T5
50. DIGATMOS SLZ files on our web site to give you the latest set of data products Page 47 Digital Atmosphere 11 11 1 11 2 11 3 Page 48 EMWIN Menu Commands Introduction This menu is provided for users who have access to the EMWIN system of data retrieval EMWIN is an excellent low cost solution for users who want 24 hour automatic access to current weather data If you do not have EMWIN and are interested in obtaining it please visit http www weathergraphics com for more information There is also a description of the EMWIN system near the end of this manual Get EMWIN bulletin This option provides an easy method to access and display bulletins stored by the EMWIN datastream Each one of the bulletins currently stored on your hard drive is presented in a tree format by region then by product then by issuing office Simply double click on any product to view it and it will appear in the panel at the right You can resize the window to read the bulletins better by dragging a corner of the window If you do not see any entries you are not using the EMWIN datastream or are saving data in a different directory see your Digital Atmosphere preferences panel You can also directly access a bulletin by typing its filename in the expert access box such as NOWOUNOK to retrieve NOWOUNOK TXT the nowcast from Norman Oklahoma When you press Enter the bulletin will be displayed Technical tip If a region abbreviation i
51. Digital Atmosphere Content A O EA ten 1 2 INtrogqucti n a a legal NOlCO o ocitio ere cate ce ss cceace cece occa tedeeceds snes iacasacaeaceescasaeeesacsceseae 2 3 Why register Where HOW MUCH ccseeeeeeeeeeeeeeeeeeeseeeeeeeeeeeeeeeeeseeeeeeeneeeeeeeeeeeeeeeeeeny 4 A UO Nea ict atta e Ea e e cine 6 4 1 Tutorial on Digital Atmosphere cccccccseseeeeeeeeeeeeeeeneeeeeeeeeeeseeseeeeneeeeeeeesessseeeeeeeeeseseeeeeneeseeeeeeeeeeeeeeees 6 5 Display Components sicsiiciccisssicis cece ndiiess eee 8 ls IT RO GUI GUO IN ii 8 5 2 Main GIN A a a ii Ei 9 5 3 Speed Buttons toolbar cirio 9 5 4 Time toolbars ati dt 9 5 5 Analysis toolbar cios ii 10 BiG SCriPt TOO baT iii in 10 Bh Pa WV OEIC A AO 11 O RAEN SS AY dra o A ted 11 5 9 Pop UP MENU iia a ii 11 6 File Men Command S sseccescei cp esca ci paeacencpscncuacpaeactnessanceecpakeceesctesanesssusacsschesanaseasacbectesaorhees 12 AITANA dat 12 6 2 Import EMWIN directory lt lt c miis cari ii ita 12 6 3 Import Weatherdish directory cc crio a init 12 6 4 Importflle ion ion laa T 12 6 5 IMPOTt Oleo id 12 6 6 Clear data dlreciO oscuras n 13 6 7 G t archived data ui A di ee eis 13 6 8 Quality CONTO is 14 6 9 View raw data A ii 16 610 Prisa ombre rene 16 6 11 Print set p cr n 17 12 O CON tii 18 6 13 Recomplle tables siira eee eee id ea 18 6 14 Preference S o vctendt pect tees seeeace specie AONA LEEENA duaceeaanceneencewtceseanctneecss 19
52. ENT_USER Software Digital Atmosphere This key can be deleted with Windows Regedit if a factory reset of preferences is desired The preferences menus are divided up into several sections each of which may be accessed by clicking once on the tabs at the top of the dialog box Just click on the tab corresponding to the settings you want to change to switch between preference pages Each tab will now be introduced individually General preferences Meteorological preferences Map preferences Station plots preferences Analysis preferences Fonts preferences Contours preferences Miscellaneous preferences General General preferences settings Also see the special topics on Default data time selection Directories Files and the Scheduler IV Ignore system interrupts IV Provide information messages IV Adjust for daylight time Ignore system interrupts This setting has been temporarily disabled in Digital Atmosphere Provide information messages Digital Atmosphere 15 2 2 15 2 3 You can use this to turn off informational dialog windows dialogs that give you information but have no bearing on how the program is executed One example where informational dialog boxes are used is when a climatological dataset is generated and you are given a tip on how to plot the data By unchecking this setting you can choose not to see these messages This will also help prevent lost data when running Digital Atmosphere unattended
53. EP reports has 30 mile resolution e NEXRAD style RCM data from RCM text messages has 6 mile resolution Since a visual clash would occur if both were plotted Digital Atmosphere requires you to pick which data you want to see This is done in the File gt Preferences gt Meteorological tab under View NEXRAD RCM rather than RAREP radar data If you have chosen to view NEXRAD RCM data you can also view other severe weather indicators including storm centroids hail tornado vortex signatures TVS mesocyclones echo heights and echo movement Note that neither of these will give you high definition radar images as seen on special radar sites and on TV These require access to the NIDS datastream which is currently encrypted according to a NOAA NIDS vendor agreement and will remain so probably until 2001 After that time Digital Atmosphere will likely be programmed to use the NIDS data Also note that because NEXRAD RCM is a binary format transmitted on alphanumeric datastreams some weather servers may corrupt the data before it gets to Digital Atmosphere This can cause a loss of viewable data Sounding Allows you to see a sounding which is a plot of temperature versus height for a given station You must have imported data that contains upper air data Extract model data Allows you to extract data gathered from FOUS style model output This forces the data into a custom data file which you can then view using Data gt Custo
54. NStAMS oo is 59 TD Ac ADS isis 60 15 4 1 General Maps Preferences cccmmnnncccccccnnncnnnnnnnncnrnncr nn nnnnnnnnnn nnmnnn nanna 60 15 4 2 JPEG Image COMpPresSSiON a aaa aaaea aaa aaa nico 61 TALA g ON A aa e a nai a ae aeae a a aaa aaae 61 15 4 4 Grid Intervals eean ea a ia 62 15 4 5 A ise cde ceceseseaceatetecvcedets tedetecterasctucecrenes sanccczeccrseeds eaaa aeaa aa anaren a ana aaan eaa naak nandana aean 62 15 4 6 Map element settini Saena la 62 190 Taton DIOS T EA TTT 63 15 5 1 Station plots tab ii aeea taaa aaae eaaa a e aee aa aa aaa ee aeara aaao Aa daaa aa a aaaea ae anaia a edenn dadaanan 63 15 5 2 Surtace plot Mod l 25 s ccs s0s secesesecceseccccsscecesssncesecesevedesacecuecdesesanutececesedescdesunuaeseectesessautessrecedscececstecetecevesens 63 15 5 3 Upper aif plot model is cet 0 cccc ce ceeetetecetecetycusicedecec seve spaucudevtvessnccescceeesectesenensteneeversduaccactdedecesecncuceceensereveenste 66 T5254 x Station titer iin DO ll a 67 UO PABA SIS A a 67 Page IV Digital Atmosphere gt a Ben AC oe e OP Om A 67 15 6 2 ISOPIOUNS A i 69 15 623 HIGHS ANG OWS ii 70 15 6 4 AmalySis ty A raaraa pa eaea a aaaea aaa aaaea aa e ses evesuceeececsteeducedesesersvienctctcesssestrsanctchdestisancadccen 71 15 6 5 Analysis parameters iii eek aaa aa a N Aaa Idea 72 A A A ET 73 AS aedie sa sconcenncenacenanncecenaseancesiaceds egg aies stnassensdesasecey 5 obsddonenenednanzeaanance satus csestbes seen pees 73
55. Regardless of the mode that Digital Atmosphere is in manual or automatic this prompts the user for a specific file to import The file will then be decoded and imported No other files will be imported The data file should consist of text bulletins containing METAR synoptic SAO FD winds aloft buoy reports or rawinsonde data After the data is imported it can then be plotted or analyzed Import directory Digital Atmosphere is a tool that lets you create weather charts using current raw data Therefore the first thing you need is a tool to get raw data into Digital Atmosphere We refer to this process as raw data import Once you import data into Digital Atmosphere via any of the possible methods explained below the program will continue to work off that data until you perform another import In other words the data will still be in Digital Atmosphere if you exit out of the program and then run it again later but once you perform a second import all the data from the first import will no longer be available Regardless of the mode that Digital Atmosphere is in scheduled or manual this command imports all files contained in the directory listed on the File Preferences General tab under Data directory The data files should consist of text bulletins containing METAR synoptic SAO FD winds aloft buoy reports or rawinsonde data After the data is imported it can then be plotted or analyzed This is the command you should use if you
56. TMODEL filename Loads a particular surface plot model Filename must be the fully qualified filename with path and extension sps ISOPLETH on joff Page 83 Digital Atmosphere Page 84 Turns on or turns off the File gt Preferences gt Contours gt Perform Isopleth option STAMP Imprints a timestamp at the top of the map that says GENERATED date time ERASE Erases all of the overlays on the map MINIMIZE The Digital Atmosphere application window is minimized MAXIMIZE The Digital Atmosphere application window is maximized NORMAL The Digital Atmosphere application window is neither minimized nor maximized QUIT Quits the program IMPORT filename Imports the specified data file filename is a fully qualified file name PRINT Prints the map to the default printer using default settings BLANK Erases the overlays as well as the basemap CLIP Copies the map to the clipboard TOPO Makes a topographic underlay on the map takes some time BASEMAP Plots the basemap CITY Plots cities COOUT Plots county outlines CONAME Plots county names HIGHWAY Plots Interstate highways U S only ROAD Plots major roads U S only Digital Atmosphere CUSTOM Plots custom overlays REMOVE Removes the last product from the display VALID PRODUCT TYPES pla ACARS plots plf Standard data plots plc Custom data plot tdy Television style data plots rad Radar plots wor Wi
57. UOY Digital Atmosphere e Upper air WMO FM 35 TEMP e Aircraft data report ACARS WMO FM 42 AMDAR e WSR 88D RCM radar coded message FMH 8 RCM e NMC frontal depiction transmission format ASUS1 KWBC DIGITAL ATMOSPHERE REQUIREMENTS Operating system Windows 95 Windows 98 Windows 2000 or Windows NT 4 0 e Processor Pentium or better recommended 486 minimum e RAM 16 MB or better recommended 8 MB minimum e Disk space Minimum 35 MB e Source of data Internet access recommended which allows access to any of numerous free data sites e Special notes Windows 3 1 Win32s and earlier versions of Windows are not supported NO NONSENSE LEGAL NOTICE The Digital Atmosphere software program and this user s guide are copyrighted All rights are reserved Unauthorized reproduction or distribution of this software is strictly prohibited and may constitute a criminal offense The user agrees to evaluate Digital Atmosphere during the 30 day trial period and determine whether the software performs acceptably By registering Digital Atmosphere with the author Tim Vasquez and Weather Graphics Technologies the user expresses that the software is acceptable The author makes no warranty or representation expressed or implied with regard to the accuracy of Digital Atmosphere its quality quality performance merchantability or fitness for a particular purpose and may not be held responsible for any damages whatsoever
58. a retrieval panel New NEXRAD site codes added to the station tables About 40 new RCM station codes have been added This fills in many radar gaps that existed in earlier Digital Atmosphere versions NEXRAD VAD VWP wind parsing has been added Simply import an RCM file and plot using Analysis for time and a valid FL for level These reports can then be plotted or analyzed Although this is an incredible tool for filling in gaps between rawinsonde stations and rawinsonde times NEXRAD winds are usually missing where there are no droplets dust insects or birds to yield a velocity measurement such as high aloft or in dry regions The level selector can contain FD winds RCM winds or both This is chosen with the R F and All buttons next to the level selector Use it when for example you want to look at NEXRAD VAD VWP winds aloft and don t want to accidentally click on an FD wind level You would simply hit the R button to pare down the list Major improvements in the Internet data retrieval panel The panel now uses true HTTP binary transfer to connect with weather data sites delivering much swifter more reliable data downloads than in previous Digital Atmosphere versions It also allows FTP sites to be accessed For those few users who need to specify a port number and or user ID amp password you must append the User ID Password and Port to the end all separated with Example ftp ftp mysite com pub data txt myus
59. ability to plot 24 hour FD contours grids Added code that prevents stack overflow error and execution of warning import when OUTPUT WRQ is missing Precipitation contours are now indicated in the legend along with the units of measure inches or mm In Internet gt Retrieve Data an Uncheck All button has been added BUILD 907 8 18 99 ATREP reports have been enabled These are usually found in upper air files and can help fill in wind patterns across oceanic regions Round AIREP reports within xxx mb of a standard level has been added When checked and the user produces a constant pressure map Digital Atmosphere will include all AIREP reports that are within the specified number of millibars of the constant pressure level being used i e an AIREP at 278 mb will be included in a 300 mb plot contour if the box is checked and the value is 22 mb or greater If unchecked then all reports have to be exactly equal to the constant pressure level being used 1 e an AIREP at 492 mb would not be included in a 500 mb chart This will help users control the quality and variety of data being included in upper air charts Data gt View Sounding and map popup menu item Show Sounding have been re enabled About 25 new EMWIN text products added to the DIGATMOS EMP EMWIN product lookup list This will add many new product descriptions to EMWIN gt Get EMWIN Bulletin Digital Atmosphere now recognizes SN intermediate sy
60. ables operation it seems that Windows locks up This is because Digital Atmosphere is sorting the Warnings table A progress message has been added and the status window no longer truncates long progress messages The ICAO WMO sorting algorithm has also been speeded up Thanks to John Glaveskas Large maps were not framed correctly when loading such as at startup This has been fixed by forcing the image object width to equal the bitmap width Thanks to Hendricus Lulofs and Geert Vandebrande Internet retrieval list DIGATMOS SLZ enhancements Added UCAR upper air thanks to Robert Schmidt added Albany buoy Digital Atmosphere now parses the RCM file when the EMWIN Scheduler is running Thanks to Robert Dale User must specify the EMWIN directory for warnings this allows compatibility with software such as RealEMWIN This option is in File Preferences General Thanks to Robert Dale Speed button toolbar can now be hidden or unhidden see View menu item Thanks to Robert Schmidt All fonts used in contouring operations are now set in Preferences Fonts under Annotations Only the font type is used the size is ignored Thanks to Robert Schmidt Internet sites which don t report the filesize in some headers such as IWIN and FSU no longer produce unusual progress results during download program now reports unknown Thanks to Verna Young and Mark Hayes Digital Atmosphere no longer tries to resize itself after generat
61. ains data about the image s latitude longitude and zoom setting If this map attribute file is not present you will get an error This is why you cannot simply make a BMP satellite photo and load it up as a map unless you ve already saved a map with similar settings in Digital Atmosphere and replaced the map BMP with the satellite BMP Save map Saves the workchart for future access within Digital Atmosphere This also saves any markings annotations weather data and contours that are on the map already as a permanent part of the map so if you intend to load this map later without any weather data you ll need to use the Erase Map command to get rid of the data before you save it If you want to save the map for your projects presentations and so forth in one of several graphics formats you should instead use Map gt Export map An important consideration is that only Windows bitmap BMP files can be saved and they are rather large File sizes can range anywhere from 300 to 700K in 8 bit color mode to 2 5 megs in 24 bit color mode So avoid saving too many unless you have plenty of disk space If you re using on the fly disk compression such as Stacker DoubleSpace DriveSpace etc these images will take up about 80 less disk space than they do when uncompressed Save Map produces one image file a Windows bitmap BMP and a very small map attribute file ATR The ATR file is necessary to load the map into Digital Atmosphere and s
62. any data scalar isoplethed fields only Digital Atmosphere always exports its output to GRID TXT The output can then be imported into spreadsheets or analyzed further by other methods The output consists of 900 points 30 by 30 representing the value at each point of X and Y in the geographic area shown in the workchart window The X axis is left right in the window pointing right while the Y axis is up down in the window pointing down This means that the highest values of X and Y are found east and south respectively The latitude longitude of each X and Y point in decimal format is shown followed by the analyzed value at that point Digital Atmosphere 17 6 Here is a sample of output from GRID TXT X Y LATITUDE LONGITUDE VALUE 0 0 42 435 107 721 1012 79998779 0 1 42 471 107 141 1012 84558105 0 2 42 505 106 560 1012 92547607 0 3 42 537 105 979 1013 08880615 EMWIN EMWIN Emergency Management Weather Information Network was introduced in 1996 to give economically strapped government agencies and volunteer civil defense groups a smart way of recelving weather data with no recurring costs The dividend for this effort is that anyone can receive the data not just government agencies EMWIN is an outstanding source of free data that is just now beginning to mature Using either a police scanner or a 3 or 5 satellite dish with cheap commercially available hardware and software you can tap into a tremendous
63. ase see the Appendix under Scripting Command Type any command in this box and hit return or press Enter It will then be executed Run script Runs a predefined script Create script Creates a script You can use any text editor instead of this button Timer off on Indicates whether the timer is off or on Press it to call up the timer configuration window Digital Atmosphere 5 7 5 8 5 9 Workchart The workchart is the large graphical space that is used to display maps plots and contours There can only be one workchart open at any one time Status bar Messages about what Digital Atmosphere is doing are displayed on the status bar at the bottom of the Digital Atmosphere screen Pop up menu Digital Atmosphere allows you to issue specific commands by right clicking on the map This action defines a location When you do this a popup menu will appear and you will have the following options that apply to the defined location Identify Warning If you have imported valid warning data this option will locate a warning at the defined location and display its text If there is no valid warning data no warnings will be found Set point This is used to define one of two points to be used in either the Quality Control function or the Show Distance function For more information see Show distance about five lines down or Quality Control in the File chapter Get lat long This will display the latitude and longit
64. ata This prevents two different radar formats from being mixed when you use Data gt Radar gt Echoes Check this box whenever you use NEXRAD RCM data such as that transmitted over EMWIN If you use the old SD RAREP code uncheck this box Round AIREP reports within _ mb of a standard level Forecasters like to see AIREP reports on upper air charts but AIREPs are rarely at an exact standard constant pressure level When this box is checked it allows AIREPs within a certain range of the active pressure level to be included on the map Usually 25 mb is a good value When it is unchecked no AIREPs will be used unless they are at the exact pressure level that s active Omit highs and lows when plotting ASUS1 frontal bulletin This should usually be left checked When you produce a pressure analysis Digital Atmosphere will automatically plot highs and lows When you use Data gt Frontal depiction ASUS1 KWBC it will plot its own sets of highs and lows which clashes with Digital Atmosphere s depiction Since the ASUS1 s fields are coarser and may differ from the isopleth fields you should generally leave this checked unless you have no surface data and want to see the ASUS1 output of highs and lows Units Temperature units Fahrenheit Celsius PFOUS data level Picks whether temperatures displayed will be in Celsius or Fahrenheit When Celsius is selected Digital Atmosphere will use Celsius units where possible please
65. ather data is shared among WMO member states who in turn set policy and procedures for sharing data with the private sector In the United States the data is distributed to the public through the National Weather Service s NOAAPORT and FOS data feeds Much of this data reaches the Internet and is available free of charge This puts affordable forecasting in the hands of millions of American citizens and business owners boosting economic productivity and earnings on a national scale Unfortunately in Europe Asia Page 93 Digital Atmosphere 17 8 Page 94 South America and even Canada long standing ultra conservative government policies make the data available only to pilots mariners and big spenders i e large corporations The Internet is the ultimate GTS though and its presence has done much to break down these economic barriers Surface weather data is transmitted in one of two main formats METAR and SYNOP The METAR format is used primarily at airports and has an hourly observation cycle It gives us the best picture of weather conditions in North America Europe and the Pacific Rim The METAR format is fairly readable and uses station identifiers prescribed by the International Civil Aeronautical Organization ICAO The SYNOP format is more detailed and uses extensive numerical coding using numerical station identifiers prescribed by the WMO and typically has a 6 hour cycle It gives us the best picture of weather in South
66. bar can be made visible or non visible View gt Status Bar The data directory is now always the data subdirectory under Digital Atmosphere Any data should always be placed in here unless it is being received by EMWIN or is a single file to be chosen manually by the user In the synoptic decoder dewpoints are now omitted if they exceed the temperature File gt Retrieve Data used to not process warning data while File gt Import EMWIN Directory File gt Import File and the schedulers did This has been fixed The number of importable files during one pass has been increased from 100 to 150 files METAR reports without times but times in FOS headers are now parsed properly Font face sizes in EMWIN Bulletins and View Raw Data can now be specified in Preferences gt Fonts A new feature Map gt Information provides detailed information about the map projection currently shown Another new feature Show distance allows users to determine the distance between two points on the map Identify each of the two points by right clicking and choosing Set point then choose Show distance The distance will be shown in nm sm and km Under the View menu the selections for Speed Buttons Time Toolbar Wind Toolbar and Status Bar are saved when the user exits the program then restored when the program is started again VERSION 2 3 1 MAINTENANCE RELEASE BUILD 930 8 29 99 Fixed problem where 24 hr precipi
67. be converted to a fully registered version even if it has already expired A key number is only available from Weather Graphics Technologies and can be given only in accordance with our registration guidelines Furthermore the key number can be computed only if the serial number is provided The serial number is unique to each computer and we can t predict what it will be If you don t supply it there will be a delay because we will have to ask you for it For most users the unlocking procedure only needs to be done once However if your company or organization specifically needs a pre unlocked version of Digital Atmosphere without the serial key procedure we offer Digital Atmosphere 2000 Professional Version It is supplied on CD ROM Click the registration guidelines link above for more info If you have any questions please E mail support weathergraphics com or call us at toll free 888 388 0070 Thanks Page 51 Digital Atmosphere 15 15 1 15 2 15 2 1 Page 52 Preferences Preferences introduction Here s where you set your preferences for how the program will operate Any changes you make are used only for the duration of the program s execution unless you place a check mark at the bottom of the page in the box named Save as default settings If you check this box the entire set of preferences is saved to your system Technically inclined users will note that the registry that is affected is HKEY_CURR
68. before saturation begins It is proportional to the actual quantity of moisture present in the air so it is often used as a universal indicator of the moisture in the air Equivalent potential temperature Equivalent temperature indicates the potential temperature of a parcel of air whose latent heat had been completely released Physically it s what the parcel s temperature would be if it were forced upwards to about 200 mb then forced downwards to 1000 mb In any given atmosphere higher values of surface or low level theta e will always yield higher instability values it s a better indicator than dewpoint or temperature so theta e is useful for seeing where an inversion or cap is about to break Pressure height menu Height Geopotential height usually called simply height is the height of a given pressure surface such as 300 mb in meters It is widely used in upper air analysis Pressure tendency Plots the pressure tendency as obtained from the 5xxxx group in SYNOP reports and the 3 hourly pressure groups on METAR reports Altimeter setting The altimeter setting measured in inches is what the surface pressure would be if it were reduced to sea level however it takes into account no temperature corrections Unlike the sea level pressure if the temperature outside varies drastically the altimeter setting will fluctuate Altimeter setting is typically what is used by the National Weather Service to report pressure readings
69. button has been added Thanks to George Sobala On the wind toolbar wind vectors as opposed to just barbs now work again Thanks to George Sobala When any map is loaded all settings not just lat long zoom are transferred to the Generate Map panel in case the user wants to tweak the map Also fixed the inverted transferred latitude Thanks to George Phillips Menu item View gt Remove last product has been added so that you can delete the last contour or plot I could not duplicate the Invalid filename on save station plot in Preferences For users that continue to have problems please go to the Preferences gt Misc tab and check Diagnostic Show filename when loading saving station plots Then when you save or load the station plot report the message that it shows SPECIAL NOTES Users may mistake station plot minus signs as decimal points particularly with pressure tendency BUILD 864 8 08 99 Added a Generate Map dropdown box on the Speed Button toolbar Clicking on any of these entries causes a map for the area to be generated using the default map width height specified in File Preferences Map The entries for the Generate Map dropdown box come from a new file called DIGATMOS MSE Users may freely modify this file Column 1 3 is for the latitude south hemisphere negative Column 5 8 is for the longitude west hemisphere negative Column 10 14 is for the zoom width in miles Column 15 65 is for the
70. can look pie shaped e Weighted Digital Atmosphere looks at the neighboring stations around a gridpoint giving it an average of those values around it with more emphasis on the values at closer stations e Barnes The Barnes method the cornerstone of the MCIDAS and GEMPAK weather workstations has a number of advantages versatility simplicity and speed Each gridpoint is assigned a meteorological value which is the result of a Gaussian distance dependent weighting function A difference field is calculated which determines how far off from reality the analysis field appears to be then a difference correction is applied to the analysis field This takes a relatively long time to compute but is one of the more accurate analysis algorithms e Cressman Each gridpoint is assigned a meteorological value which is the result of a distance dependent weighting function The Cressman analysis method is similar to the Barnes technique however it makes successive corrections using a smaller and smaller radius of influence to eliminate all errors It takes more time but the results are good In data sparse areas it is common for there to be erroneous contours especially if Digital Atmosphere is tasked to determine the best station spacing Strengths It s sophisticated and flexible and it may retain more mesoscale structure Weaknesses It can t resolve short wavelength components it can require a large amount of time and it can fail wit
71. ches mm Base Determines the base value that the intervals are based off of For example if you use an interval of 5 degrees a base of zero will give 0 5 10 15 20 25 degrees If you use a base of 2 degrees you ll get 2 7 12 27 etc Digital Atmosphere 15 9 15 9 1 Always reduce the base to the lowest common denominator as close to zero as possible Interval Represents the contour step interval the numerical difference between each contour AI Automated interval If y is entered Digital Atmosphere will override the base and interval settings and choose the ones that will give the clearest view of the data field Style Indicates the linestyle that will be used to draw the contour Acceptable values are solid dash or dot Radar echoes must be either solid clear bdiag fdiag cross crdiag horiz or vert Color Indicates the color of the contour Here are the acceptable color settings you can use black maroon green yellow olive navy purple fuchsia teal gray silver aqua red lime blue white Miscellaneous Misc tab General Meteorological Maps Station Plats Analysis Fonts Contours Misc l Advanced internet settings Proxy host Proxy port Color gradient fills Photorealistic topography Phi Ph2 Scale Offset Y Smooth final image good for tight zooms Red pb joo hh pb IV Re overlay geography Green bp fpo po po Blue fao 180 Po po Advanced internet
72. control of map generation Digital Atmosphere 7 4 Generate map by lat long t Hap Settings Lat Long iof x re A Scale Longitude 97 3000 nm Latitude 38N 14 Ej gt Map size pixels Advanced map settings Offset Aspect Width rso x 0 Ni L Height 550 Y Lv Location quick pick Zoom quick pick Size quick pick United States Global scale 250 x 250 Canada Britain Synoptic scale 350 x 350 i 590 x 420 Australia Subsynoptic scale 590 x Asia Meso alpha scale 750 x 550 Africa South America Meso beta scale 974x718 Pacific Russia Meso gamma scale 1550 x 1150 This is a powerful tool that replaces the map contained within the selected workchart with another map Once you choose this command you ll see a settings panel appear This is where you choose how your map should look All maps are generated using an orthographic satellite view projection e Latitude Sets the latitude for the center of the screen in degrees e Longitude Sets the longitude for the center of the screen in degrees e Scale Sets the width of the map in either miles or kilometers e Map size height width Allows you to specify how many screen pixels wide and tall you want the map image to be You may also wish to choose one of the map size speed buttons If you want an exceptionally detailed image you may want to choose one of the higher settings The 1550 x 1150 size yields exc
73. d EMWIN signal on GOES 8 and 9 will be cancelled on May 31 1998 and the 9600 baud signal will go to an even higher power level WHAT YOU NEED Geostationary satellite signals are weak so you ll need at least a 3 foot dish a low noise adapter a downconverter and a radio All of this is an investment of about 500 to 1000 Zephyrus Electronics of Tulsa sells a special EMWIN receiver that basically acts as a black box for all of the radio elements you just hook one end to the satellite dish the other to your PC COM port and plug it in WHAT S IN IT FOR YOU You can receive the broadcast from almost anywhere in the western hemisphere whether you re in an igloo in Greenland or in the swamps of Louisiana You re directly linked to the EMWIN datastream and are receiving it at the full 9600 baud meaning you get all products And there is no fee for receiving the data THE PITFALLS The cost of the equipment is the only pitfall Furthermore the requirement for a satellite dish may be a problem for apartment dwellers OPTION 2 OF 2 Rebroadcast reception Some local government agencies mostly in the south United States may have an EMWIN rebroadcast in your area THE SCOOP A rebroadcast station receives the EMWIN datastream via satellite and transmits selected text graphics and imagery products as an audio signal on a dedicated VHF or UHF radio frequency Some stations also insert products such as school closings road conditions and so fo
74. d for a height in millibars Digital Atmosphere will examine the 3 D grid and analyze the data at this height The power of an override is that it lets you visualize the height at any millibar level 434 570 883 mb etc and it makes use of all available data including TTBB significant level data to accurately represent data at those levels Roaming sounding To enable this option you simply choose Analysis gt Roaming sounding A blank sounding will appear As you move the mouse across the workchart a sounding valid for that location will appear on the sounding chart This is an impressive way to visualize Soundings across a wide region without having to call up individual soundings and figure their relationship to the weather patterns For more information see Roaming Sounding Cross section Simply drag across the workchart to define a geographical line and choose Analysis gt Cross Section A cross section window will pop up You can then choose to visualize various meteorological parameters along this segment For more information see Cross Section Digital Atmosphere 9 10 2 9 10 3 9 11 9 12 9 13 9 14 9 15 Roaming sounding Causes a sounding to appear When you move the mouse over the horizontal area workchart the sounding plot will change accordingly to indicate the sounding appearance at that particular location When you are finished click Close on the sounding window to stop roaming mode Cross s
75. d the sea level pressure contours aren t plotting correctly you ll want to increase this value Earth s rotation constant Specifies the earth s rotation in radians per second which is normally set at 0 000007292 Naturally there is no need to change this unless you want to tinker and see the results The earth s rotation constant is used in the Coriolis parameter equations which are used for geostrophic wind calculations and calculation of absolute vorticity Hitting reset replaces any entered value with the Earth s rotation constant Gravity constant Specifies the gravity on the Earth s surface which is normally set at 9 806 m s 2 There s no need to change this unless you want to tinker and see the results Gravity is only used in the calculation of geostrophic wind based solely on height contours Hitting the reset button replaces any entered value with the Earth s gravity constant Page 59 Digital Atmosphere 15 4 15 4 1 Page 60 Maps General Maps Preferences Also see the special topics on JPEG image compression Lat Long grid Grid interval Default size and Map element settings Make coastlines double wide TF Plot ocean fill crosshairs Y Topography use avg elev rather than max IV Fill outer space uses general plot color IV Label latitude longitude lines Make coastlines double wide By checking this box any maps that you generate will look more professional due to thicker coastlines However you ma
76. ded capability for user to modify Gradient Fills in analysis in File gt Preferences gt Misc Added capability to import and plot SATOB observations NOAA NESDIS format Added scripting commands for ISOPLETH and GRADIENT Added extra surface station plot element which is available to user in extreme lower left of plot Added import of sea surface data from SYNOP reports Changes have been made to allow saving and loading of upper plot models Added capability to plot h and Nh code forms from SYNOP corresponding additions in Preferences Changed temperature and precipitation units to a single English or metric choice Added streamlines Added capability to plot fronts highs and lows from ASUS1 KWBC bulletin VERSION 2 3 3 MAINTENANCE RELEASE BUILD 1015 10 1 99 Quality control was improved to change point point clicking to mouse dragging A distance meter enhanced Page 99 Digital Atmosphere Page 100 this capability VERSION 2 3 2 MAINTENANCE RELEASE BUILD 989 9 23 99 The main purpose of this release was to get rid of a memory violation reported by six users which consisted of various forms of Invalid pointer and Access violation errors when Digital Atmosphere was started This was finally traced to coding errors in the creation of new maps In addition to a fix for the problem this release has some additional enhancements Invalid pointer and access violation errors eliminated Status
77. descriptive name Users may add saved maps to this list by simply leaving the first 3 columns blank then for a descriptive name use an asterisk followed by the filename without any dot or extensions for example mymap Added a Preferences entry under the Map tab for Default Width and Default Height This specifies default image size settings for new maps that will be generated Reworked the Preferences Station Plot Save segment as some users have reported that the plot model is incorrectly saved Could not duplicate this problem but made adjustments to code Eliminated problems with importing FD and Model data this was a consequence of improvements made to the data import algorithms in Build 849 Build number now shown on splash screen PROBLEMS REMAINING Internet links except for Retrieve Data are dead locks up using data retrieval window with FSU SAO ticked SUMMARY New files required to run this build DIGATMOS MSE BUILD 849 8 6 99 Synoptic and buoy recognition module reworked You should see a greater number of synoptic observations and especially buoy ZZYY observations that now work Please let me know if you see any problems Eliminated Access Violation during View Raw Data Find Corrected code to link in a missing component Digital Atmosphere Thanks to John Glaveskas Trevor Cousens Geert Vandebrande Legend was not cleared when generating a new chart this has been fixed Thanks to Geer
78. e Off O ERVIN C Internet retrieve Internet data every eo min Archive data Enable imagewrites M Autoname imagewrites Scheduler Off This is the default setting Digital Atmosphere operates in manual mode and does not look for any incoming weather data Scheduler EMWIN If selected Digital Atmosphere will look in your EMWIN directory every 60 seconds and check for new data If a new file is detected it will be imported immediately and all charts will be refreshed Digital Atmosphere examines data in the EMWIN Data Directory with the EMWIN Surface Data filename and the EMWIN RCM Data filename and all warnings in the EMWIN Warning Directory TOR SVR FFW etc Scheduler Internet If selected Digital Atmosphere will be tasked to periodically retrieve data off the Internet and refresh its workcharts The interval is determined by the value specified in retrieve data every ___ minutes So that the host servers don t get overloaded we have designed this scheduler so that downloads cannot be made more than once every 15 minutes Scheduler Archive data When the scheduler receives new data it examines this setting If this field is checked Digital Atmosphere will archive the data automatically The file will be placed in the Archive Export Directory and will have the filename YYMMDD HHZ i e Oct 7 1999 at 1600Z will be placed in 991016 06Z The filetime equals the current system UTC time Univ
79. e actual wind vector and the geostrophic wind vector Ageostrophic wind is stronger when the pressure and wind fields are out of balance Much of the vertical motion in the atmosphere can be attributed to ageostrophic flow Q vector The omega equation is a diagnostic for the total time derivative of pressure It allows synoptic scale vertical motion to be accurately estimated by analyzing temperature and wind fields above the boundary layer The omega equation is defined as shown here where the term on the left side of the equation indicates vertical motion On the right side the left term is proportional to differential vorticity advection while the right term solves for thickness advection So positive differential vorticity advection plus warm thickness advection equals upward vertical motion A Q vector roughly depicts the ageostrophic horizontal wind that develops in order to maintain the thermal wind balance in a developing synoptic system Q vector convergence implies synoptic scale upward vertical motion and Q vector divergence implies downward vertical motion This can be interpreted either by looking at the Q vectors or running a derivative convergence field together with Q vectors Also where 850 mb Q vectors cross the 850 mb isotherms moving towards warmer air frontogenesis is indicated Q vectors crossing into colder temperatures indicate frontolysis This quality is known as the geostrophic frontogenesis function use 700 mb levels
80. e tel et treat eat eases ee ete Saaana aa aaia ardada a aare 31 SO WAN o a eg e o hc ae 31 8 6 Frontal depiction ASUS T ia 31 8 7 CONVECUVE QUIDOKS di 33 8 8 RAGAN ot aci 35 8 39 SOULE Gece eee ae aa a aa ee A Ud ce ccs Uae ee an cache ahah 35 8 10 Extract model data a A eset 35 9 Analysis COMAS do 36 A aido UCA a A oe ate A eh Lek 36 9 25 AnalYSIS BASICS wats ii lid 36 93 PMA Y MES A A A tada 37 9 4 Temperature MENA 0 A tad 37 9 4 1 Wind Cll ee cesses sacs Sage ceestecs e nce teccncecsuctecccceeteecedenedetededetatecetecetecedeeninsedenccecusdseesectucstheatieettecancutrestes 37 9 4 2 TOM PO rater 2 3 i322 aa aaa a a aean aa ede ssendtenetesevesszusuteddee cenebbeteterstetstananedasveceuecavecutetecsietefiaccetadeSatens 37 9 4 3 Potential temperature ic aia 38 9 4 4 Thickness 1000 500 MD ooo acacia da oia aia ai nnmnnn nnmnnn nnmnnn 38 9 5 Moisture MEA A det p cde st edecuaseeevaaes 38 QUIM Xie ccc case ete sevens e a e e a a aa a e aa aa aaa r aaa r aves a ar deve eeveretecad eacee cedenesabedes vey Naana 38 Page Il Digital Atmosphere 9 5 2 Heat nd anoo a a a a a e aaa 38 9 5 3 Relative humidity ais 38 9 5 4 MIXING AAA E ar e aa aaraa ets nace aaa aaa aaae aaae ce Aaaa eaea aaa aaaea eaaa inaia 38 9 5 5 Dewpoint temperature nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn nnmnnn nnmnnn nnmnnn nnmnnn 39 9 5 6 Equivalent potential temperature coo0nnncccccnnnnnnnnncccc rr 39 9 6
81. e temperature feels like to a person based on the free air temperature and the wind speed The wind chill always equals the free air temperature when the winds are 4 knots or less Temperature Analyzes the free air temperature in either degrees Fahrenheit or degrees Celsius Page 37 Digital Atmosphere 9 4 3 9 4 4 9 5 9 5 1 9 5 2 9 5 3 9 5 4 Page 38 Potential temperature Potential temperature is what the temperature of the air would be if it was forced to the 1000 mb level In other words it eliminates the effects of elevation allowing you to effectively compare temperatures in mountainous areas using a common temperature measurement Thickness 1000 500 mb This option plots the difference in geopotential height between the 1000 and 500 mb levels in meters Upper air radiosonde data must be imported in order to view this field Moisture menu Humidex This is similar to the heat index but is often used in Canada It equals H T 0 5555 e 10 where T is the temperature in Celsius and e is the vapor pressure in mb Further information is available in Humidex A method of quantifying human discomfort due to excessive heat and humidity by J M Masterton and F A Richardson CLI 1 79 Environment Canada Atmospheric Environment Service Downsview Ontario 1979 Heat index The heat index is an empirical equation describing what the temperature feels like to a person based on both the
82. e this data by any means using third party programs The custom data field must always be placed in the file CUSTOM DAT in your Digital Atmosphere directory It should be structured according to the following example THUNDERSTORM DAYS ALL MONTHS US AL Bir 722280 33 567 86 750 57 US AL Oza 722269 31 283 85 717 73 x US AL Hun 723230 34 650 86 767 54 X US AL Mon 722265 32 2383 86 367 56 E Here is a breakdown of each row and column Row 1 A header that will be used by Digital Atmosphere to title the field Row 2 Data as explained below in data row format Data row format Column 1 19 Not used The user may wish to put location names here Column 21 29 Latitude degrees and thousandths negative is southern hemisphere Column 31 39 Longitude degrees and thousandths negative is western hemisphere Column 41 49 Primary data value Column 51 59 Secondary data value Ingesting a scalar field When a simple scalar field such as temperature pressure wind speed etc 1s imported the value must be placed in the primary data value field and the secondary data value field must contain an asterisk character Ingesting a vector field If a numerical value is detected in the secondary data value field Digital Atmosphere Page 29 Digital Atmosphere 8 3 Page 30 will assume a vector field such as wind u v component is being ingested The primary data value must assume a direction relativ
83. e to true north such as wind direction and the secondary data value must assume a magnitude such as wind speed When vector data mode is being used analysis calculations will use wind barb symbology to represent data elements Table plots Plots weather data from tables generated by third party sources Various weather agencies such as the Australian weather service generate lists of rainfall and temperature data Digital Atmosphere has the capability to import these based on the settings in the table template file DIGATMOS TPL in your Digital Atmosphere directory A list of valid data types will be shown only if the most recent import operation has found data defined in the template file In the data file itself any table containing weather data should have each line of data corresponding to a geographical point and must have a latitude longitude and anywhere from 1 to 50 data values for that point Template file entries DEF starts the definition of a table Give the table a name in T1 this name is used for display purposes LEG defines a line that can be used as a legend for the table such as a line that contains a date or valid time Specify a keyword that is to be located on the line When encountered it will be used in legends FLG is a scrap of text which when encountered during importing tells Digital Atmosphere that it is about to encounter a table This flag must be encountered before any data can be imported Speci
84. eate a map centered on a particular station This is similar to how maps are created in WeatherGraphix Maps can still be generated using lat and long Page 108
85. ecked I This is an example of the font above except with transparent unchecked A background color is used to backdrop the font If transparent is checked then the map below would bleed through under the font Highs and lows Highs and lows IV Use NMC font Use NMC font When checked this will allow Digital Atmosphere to use NMC fonts which are the fonts used on various DIFAX products They are easily recognized by most experienced meteorologists Leaving it unchecked will allow Digital Atmosphere to use the font specified by Annotations in File gt Preferences gt Fonts H i f 1 Regular Digital Atmosphere font Digital Atmosphere 15 6 4 up 102 NMC font Analysis type Analysis type C Weighted C Nearest Neighbor C Cressman Specifies which mathematical algorithm is to be used to analyze the data field e Nearest neighbor This is by far the quickest and most users will use this setting Values are mapped to the closest gridpoint then are mathematically expanded to neighboring unfilled gridpoints in a cyclical manner Afterwards a selective smoothing operator smooths gridpoints performing more smoothing iterations performed on gridpoints that are further from representative data areas and less or no smoothing passes where data is close to a gridpoint Strengths It s fast and always works Weaknesses Data void border areas look linear and data void interior areas
86. ection If the mouse has been dragged across the horizontal workchart to define a geographical line and a 3 D analysis has been generated this will allow you to display atmospheric cross sections for the given line When you are finished click Close on the window to close it MVFR IFR weather Plots areas of MVFR or IFR conditions Custom data field Analyzes a custom data set from your CUSTOM DAT file see the appendix on Custom Data for full details The contour base and interval are automatically determined Export last analysis This item has been discontinued Digital Atmosphere always outputs its analysis to GRID TXT in the Digital Atmosphere directory For more information please see the Appendix under Using Exported Analysis Grids Wind field Computes an observed wind grid as reported in the weather data The arrow of the feather or vector points towards where the wind is going Geostrophic wind Computes a wind grid based on the pressure or geopotential height field Geostrophic wind is based on the pressure gradient and the Coriolis effect and due to the effects of friction it is always higher than the observed wind speed Geostrophic winds are useful for getting an idea of how strong the winds will be later in the morning when air flow is being suppressed by radiational inversions Page 43 Digital Atmosphere 9 16 9 17 9 18 Page 44 Ageostrophic wind This is the vector difference between th
87. ellent printed maps that are suitable for publishing If this image size is larger than the screen you will be provided with scroll bars to roam around the image However note that large maps place a burden on your computer s resources and too many large maps open at the same time may cause warnings or errors Avoid setting sizes larger than 2000 pixels Offset advanced map setting Most users should leave these at a value of zero Advanced users may want to change them to put the map off center from the projection center usually to align the image with satellite photos and so on Page 21 Digital Atmosphere 7 5 7 6 Page 22 e Aspect advanced map setting Most users should leave these at a value of one Advanced users may want to change them to compress or expand the map geometrically by a certain value in the X or Y direction usually to align the image with satellite photos and so on Location quick pick Click on any of these buttons to automatically set an appropriate latitude longitude and scale for a commonly used region e Zoom quick pick Click on any of these buttons to automatically set a map scale based on a meteorological scale type Global scale sets a width of 8300 nm synoptic scale 4000 nm subsynoptic scale 3000 nm meso alpha scale 1500 nm meso beta scale 700 nm and meso gamma scale 200 nm e Map size quick pick These give quick predefined map size settings Generate map by station Select statio
88. ername mypassword port If you decide to specify a port number you must specify a username and ID New formats added to Export map In earlier versions you could save your map as a BMP or a JPG In addition to those you can now save PCX PNG and TIF uncompressed and packbits formats The Digital Atmosphere packbits TIF format generally offers the best format for desktop publishing purposes The GIF and LZW TIF formats were not included because they are proprietary technologies and require licensing from Unisys Map can be copied to the clipboard This can be found in the menu under Map and Copy to Clipboard When the map is in the clipboard it can be pasted into other Windows applications Fonts in Preferences improved The interface has been changed slightly and we have added the ability to let you set annotations fonts which are seen when you plot custom map points and city overlays and county name fonts County name overlays added You can now add county names on your map The county name text will be truncated automatically according to the map scale to see more of each county name make a more zoomed in map The font color is controlled by the county overlay setting in Preferences Map and the font name size is controlled by the county name setting in Preferences Fonts Custom geography added This is done in the WeatherGraphix style with custom geography residing in DIGATMOS PLR Edit this file to make cha
89. ersal Coordinated Time not the valid time of the data and the conversion from your system clock to UTC is based on whatever time zone settings are in effect in your Windows Control Panel under Date Time Scheduler Enable imagewrites When the scheduler receives new data it automatically refreshes the workchart Would you like this workchart to be saved to disk each time If unchecked this will not occur If checked the workchart will be automatically exported imagewritten to disk using the settings provided in Archive Export Directory Imagewrites File and Autoname imagewrites Scheduler Autoname imagewrites When the scheduler receives new data and Enable Imagewrites is checked this determines what the imagewrite Page 55 Digital Atmosphere 15 3 15 3 1 Page 56 filename will be If unchecked the graphic image will be automatically written to the Archives and Imagewrites Directory using the name given in Imagewrite File this is a fixed name the old file is overwritten each time If checked Digital Atmosphere will automatically write the image to the Archives and Imagewrites Directory using the name format YYMMDDHH ext where ext is the filetype obtained from the Imagewrite File entry jpg pcx tif bmp or png and YYMMDDHH is the UTC year month date and hour i e a new filename is generated every hour TECH TIP EMWIN Scheduler Although the EMWIN Scheduler was designed for those recei
90. ete Site button You can also add a new site by clicking the Add Site button You will then be prompted to enter the site name and URL for the data Many sites especially for surface and upper air data have a filename that is dependent on the Greenwich Mean time of the observation To support this Digital Atmosphere lets you insert time tokens into a filename For example if you entered a product that had a URL address of http www weatherdata com Hdata txt Digital Atmosphere would automatically substitute the current UTC GMT hour in place of the H So if it was 9 pm EST 02Z Digital Atmosphere would retrieve http www weatherdata com 02data txt Here is a complete list of all the UTC time token combinations you can use Character 1 mode This hour S Last hour Character 2 time M Month Digital Atmosphere D Day H Hour X Rawinsonde hour rounds down to 00 or 12 S Main synoptic hour rounds down to 00 06 12 or 18 Intermed synop hour rounds to 00 03 06 09 12 15 18 21 F Frontal hour for ASUS1 KWBC frontal position bulletin rounds to 01 04 07 10 13 16 19 22 xxx note that some servers do not produce a ASUS1 at 222 Although Digital Atmosphere automatically figures the current time tokens before you retrieve data you may want to override them This is handy if you want to see data for an earlier hour All you have to do is change the numbers that are dis
91. f Europe January mean high temperature erratic COULD NOT DUPLICATE Problem Pressure tendency shows labels only for positive numbers COULD NOT DUPLICATE COULD NOT FIX YET WILL ADDRESS IN UPCOMING VERSIONS Problem Timer does not work when a screensaver gets focus NO SOLUTION Problem Europe army weather server causes DA to hang NO SOLUTION YET Problems with importing radar when it appears after surface data in raw data file NO SOLUTION YET Problems with 333 group SYNOP rainfall when a 111 6xxxx group is present NO SOLUTION YET Some problems that have been reported with plotting of warnings NO SOLUTION YET VERSION 2000 beta 2 11 25 00 Sea data now nullified in METAR reports so garbage doesn t appear in station plots with sea elements Beta bug with Analysis gt Wind gt Wind Speed not working is fixed Celsius English beta problems fixed in plotting and climatology extract Beta testers need to check their station plot elements and change TEMP DWPT VIS to match valid choices Elevation can now be plotted in meters or feet according to English metric preferences Digital Atmosphere Climatology gt Extract Data now gives option of plotting the data or analyzing it Additional options in File gt Preferences gt Analysis to let users specify isopleth fonts as small and or negative Added remaining font files as well as font preferences Fixed problem with streamline thicknesses changing randomly Added option i
92. for convenience The cost of the CD ROM version is an extra 10 plus 5 shipping and it will usually arrive within a week PROFESSIONAL VERSION Digital Atmosphere 2000 Professional Version is available for 199 no discounts or special upgrade prices permitted It provides the single added benefit of eliminating all serial key validation This makes it especially geared for industrial government and university environments where serial key validation procedures are unacceptable and a pre unlocked solution is needed This version is provided only on CD ROM and it does include the Operational Mesoanalysis PDF book listed above Additional site licenses can be purchased anytime at a significant discount 45 per license HOW TO REGISTER To register follow any one of the methods below Note that we accept credit card Visa Mastercard check cashier s check money order international money order and Government IMPAC cards Purchase orders from government agencies and A rated corporations institutions are accepted subject to verification and must be faxed or mailed in writing e Telephone Use your VISA or MasterCard and call us at toll free 888 388 0070 or 405 573 0700 e Web site Use your VISA or Mastercard and fill out the secure order form located on the World Wide Web at http www weathergraphics com buy htm and it will be automatically transmitted to us Orders are usually processed within 24 hours E mail Use your VISA
93. fy the scrap of text in T1 BEG is a scrap of text which when encountered during importing tells Digital Atmosphere that a data table is starting right now Put the scrap in T1 and define the column where it must be seen in V1 and the length of the scrap in V2 Data import always ends on an empty line DAT is specified for each data element that appears on a line Give the field a name in T1 this is used only for display purposes Define the beginning column of the data in V1 and the length of the data in V2 MIS specifies characters that are used to denote missing data LAT specifies where the latitude decimal only is found Put the column start position in V1 and the field length in V2 LON is similar to LAT but for longitude Example DEF Australian rainfall data LEG Observations FLG IDCLRD00001 BEG 66 2 MIS A LAT 67 6 Digital Atmosphere 8 4 8 5 8 6 LON 60 6 DAT 1 10 Date DAT 12 6 Stn_num DAT 23 40 Name DAT 81 5 Precipitation_mm DAT 87 1 PP DAT 89 1 DC DAT 91 1 OF Television plots Plots large font displays of temperatures Very important Before you can use this option successfully you will need to configure the DIGATMOS PLL file correctly with any text editor such as Windows Notepad DIGATMOS PLL is in your Digital Atmosphere directory The structure is as follows where the first column is the ICAO identifier for METAR data and the
94. ginal weather data from online services the Internet etc that is fed into Digital Atmosphere when the user selects File Import First the file is copied and filtered to produce a clean data file C DIGATM DATA USR and then data is imported producing a formatted data file Station plot A small grouping of numbers and symbols that depicts the observed weather at a given location Plots are not drawn they are plotted Status panel The window that shows the clock the active level data display options and import filters Sterilized data file A temporary file containing original raw data that is produced whenever the user imports data It contains no control codes or extraneous characters The sole purpose of a clean data file is for the File View Raw Data command and for Digital Atmosphere functions where English language bulletins are drawn on the screen such as tornado watches convective outlooks etc Weather data plots and analyses do not come from this file but from the formatted data file Topography The multicolor shades that can be manually drawn on landmasses to represent terrain Upper air Involving any level besides the surface Map attribute file structure For technically inclined users only This file ending with the file extension ATR is associated with each map which is saved to disk The attribute file is structured as follows Number Purpose real Central latitude degrees real Ce
95. gits multiplied by 1 so 34 000 ft equals 34 The title parameter is optional and contains a text title that will be placed in the legend Derived fields are not supported at this time MAKE lat long zoom width height Makes a map using the given coordinates Lat is negative in the southern hemisphere Long is negative in Digital Atmosphere the western hemisphere Zoom is a value equal to 3964 x where x is the width of the map in statute miles Width and height are the map sizes in pixels GENERATE location Makes a map centered on a given location The location which is not case sensitive must be a valid entry in the Generate Map dropdown menu on the speed buttons toolbar This in turn gets its valid entries and lat long zoom data from the DIGATMOS MSE which you can edit if a map does not appear right and map size settings are from File gt Preferences gt Maps gt Default Size CENTER siation zoom width height Makes a map with the chosen station in the center of the screen Zoom is a value equal to 3964 x where x is the width of the map in statute miles Width and height are the map sizes in pixels DOWNLOAD url filename Downloads a product from an Internet source The url is the fully qualified RFC 1738 standard URL including filename and filename is the full local name where the file will be stored Example download ftp userid password ftp mydomain com anonftp pub out jpg c da20 bin map in jpg UPLOAD url
96. gures out a carefully averaged value best representing what the value at that gridpoint probably is The Barnes algorithm goes a step further by going back and seeing how incorrect its mesh turned out to be then adjusting that to produce a final analysis The Cressman algorithm does the same thing but it also begins its analysis using values at stations over a wide area then gradually tightens up its analysis running corrections and using values at stations over a progressively more narrow area This allows Cressman to accurately resolve large waves as well as small localized waves Let s now take a closer look at each type of analysis Primary fields Primary fields are your basic atmospheric properties When you click on any primary field Digital Atmosphere immediately examines which derivative fields are checkmarked if any and immediately begins analyzing Most of these properties are scalar variables having only magnitude so Digital Atmosphere will show them to you using isopleths contours You may instead display the gridded values themselves or a gradient color field However some of these properties like observed wind and Q vectors are vector fields having both magnitude and direction so they are displayed using wind feathers or drawn vectors Colors and settings are for the most part defined in File gt Preferences gt Contours Temperature menu Wind chill The wind chill is an empirical equation describing what th
97. h extreme data distribution Page 71 Digital Atmosphere 15 6 5 Analysis parameters Smoothing coefficient 4 a gt 0 50 Smoothing passes KT y ni Surface radius 4 fo 400 nm Upper radius 4 _ gt 400 nm ES i Mm 2o30 Reduction a Fls de Smoothing coefficient Sets the mathematical value of s for the smoothing equation This affects what kind of wavelengths will be filtered in the analysis grid Smoothing passes Determines how many times a smoothing operator will operate whenever it is called With this you can set how smoothed the maps will look when the analysis is complete This should be set to 1 or to a low non zero value Surface radius Determines a radius of influence used in the Weighted Cressman and Barnes analysis method for surface data This value should approximate the average spacing between surface stations Upper radius Determines a radius of influence used in the Weighted Cressman and Barnes analysis method for upper air data This value should approximate the average spacing between upper air stations Gamma Determines a gamma used in the Barnes analysis method for upper air data Reduction Determines a reduction value used in the Cressman analysis method for upper air data Page 72 Digital Atmosphere 15 7 Fonts 15 7 1 Fonts tab Press any of the buttons to make changes to the fonts that are used on Digital Atmosphere workcharts Page 7
98. hen press Calculate Note about actual pressure A very important note when you are asked for Actual Pressure this indicates the actual pressure of the parcel not the sea level pressure unless you re really at sea level You can find your actual pressure by simply calculating Station Pressure mb and entering your altimeter setting pressure in inches as provided in public weather reports and your elevation in feet An example In Denver Colorado your elevation is 5300 ft and the pressure is 29 96 inches This yields a station pressure or actual pressure of 834 8 mb You can then use this value in calculations which ask for actual pressure Recompile tables This option is used to recompile station tables from scratch Most users don t need to use this command since compiled tables are already provided with Digital Atmosphere Itis used only when you change the station listings in DIGATMOS STN and you want these changes to be enabled To modify DIGATMOS STN you ll need a standard text editor such as MS DOS EDIT Always be absolutely sure that you save it as a ASCII text file or you will corrupt your installed copy When you have finished your changes you can use File gt Recompile Tables at any time to regenerate the internal listings It takes about 5 minutes the sorting algorithm is a demanding operation Once the procedure is finished Digital Atmosphere will make use of the new changes You may Recompi
99. his doesn t work you can obtain support at the following locations E mail is usually preferred since this gives us time to research your problem We always appreciate feedback and notification when users find bugs since we are committed to producing the best possible product E mail support weathergraphics com Mailing list _http www listhost net 8 1 guest RemoteListSummary wx_software Telephone 888 388 0070 Fax 405 329 5275 Mail Weather Graphics Technologies P O Box 450211 Garland TX 75045 Page 78 Digital Atmosphere 17 17 1 Appendix Terminology If you want to be an expert with other Digital Atmosphere users and with tech support here s the definitions of some of the terms that we use Active level At any given moment Digital Atmosphere will only perform analysis or plotting operations for a certain type of data or height level such as surface 300 mb NGM model output etc Active level describes which one is the current one You change it using the Level setting on the Time Toolbar Analysis See objective analysis Derivative field The vorticity divergence or advection of a selected primary field Dialog box Any box window that pops up on the screen temporarily asking you to enter or click something Formatted binary data file The end results of File Import where tables of raw data are stored on disk and made available to the plotting or analysis routines These files consist of compressed data
100. hould stay in the same directory as the BMP file Advanced users can learn more about ATR files with Map Attribute File Structure in the Appendix Once the BMP file is saved you are free to use any graphics editor to tweak or annotate the image Note that you must re save it as the same type of graphics format it was in a BMP with a color depth of 24 bits or Digital Atmosphere will produce an error message when it attempts to load the image Export map This command is exactly identical to Save Map except that no map attribute file ATR is saved Therefore it is designed to save maps for use in your projects presentations or reports The output format can be selected under Save as type Here are the different filetypes you can save e BMP Windows bitmap This is a universal format but large filesize Note that it creates 24 bit files that are not compatible with some older graphics viewers particularly those written before 1996 e JPG JPEG Tightest compression but details may be lost Compression settings are specified in File gt Preferences gt Maps gt JPEG image compression e PNG Portable Network Graphics This is similar to GIF good compression Only browsers written after 1998 or so will recognize them though e PCX ZSoft Paintbrush It s an older format that s a defacto standard among ancient DOS programs You should always use BMP instead of this format when possible e TIF TIFF Packbits This is best for imp
101. i 44 9 19 ise tr picanadly SIS e raaa na 45 10 Internet Menu Commands ss ssssnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn nnmnnn nna 46 10 1 INtFOGUGTIONN ioiii aana A Ai aia 46 MO22 Retrieve dadta a a ES E eee ence AM een 46 11 EMWIN Menu Command cccccccnccnnnnnnnnnnnccnnnnnccnnnnncnnnnnnnnnnnnnnnnnnnnnrnrnnnnnnnnnn nr nr rrrrnnnnnnnanannnnnns 48 11 1 INTFOUCHTON 200000 48 11 2 GetEMWIN bulletin oc eh ee ee ees ei eee en eee A ies a 48 Page Ill Digital Atmosphere TTS Display MAA A a a ale ea oh ea acs ace at att Saal eats 48 12 Climatology Menu Commands ccccccccnnnnnnninananonincnononnnnnnnacncnnr rre 49 TE Gated ia 49 A A O O O T 49 A iets E S 49 13 Window CommandsS aia 50 13 1 Add remove TOOIDANS ii A A A ak ee ee 50 13 2 Remo ve last PO UC E ia 50 14 Flelp AMAS E 51 A T a Fa a Sle ee a a feed dace cet chcs TT 51 ADs PRETCIONCES ica 52 15 1 Preferences introduction ii iia 52 Rmn ce ee ect ee edt ae ionian Arana Si 52 15 2 1 General preferences settings ooomommnnccccnnnnnnnnncacccrrn nen 52 15 2 2 Default data time selection o0n nnnmiccccnnnnnccccncncnnnnnnnaccrrrrcrnn rre 53 152 3 Director eSa a diarias 53 rA A E A ld 54 TLC A A da 55 15 3 ls P P e PA 56 15 3 1 General Meteorological Preferences 000mmmmmnnsiccccrrecnnsnccrrnccrrrrrrnnc rr rr 56 W532 UMS AAA nm y yn ao 57 15 3 3 FOUS data level iii de 58 15 3 4 Parcel lift CAICUIATIONS oi iia 58 15 3 5 Physical CO
102. ic to Digital Atmosphere and may occur with other applications that make extensive use of the PCL driver HP Laserjet 4si HP Laserjet 4000 HP Laserjet 4 Windows 95 Landscape mode tends to generate blank pages and portrait tends to print garbled maps when using PCL5 PCL 6 tends to fix the problem Windows 98 No problems Canon BJC 240 Windows 95 Problems with Canon BJC 240 with latest driver with maps coming out extremely garbled in both landscape and portrait modes Windows 98 No problems Canon LBP 660 Windows 98 Prints blank pages Print setup This function is used for specifying how you want your printer to print maps These panels will vary based on what type of printer you are using One option that is useful for some printers is the Graphics Resolution When you lower this value it will help you send extremely detailed charts to printers that keep producing out Page 17 Digital Atmosphere 6 12 6 13 Page 18 of memory errors or blank pages Calculator Do you need to find a wind chill value A mixing ratio A theta E No problem Digital Atmosphere s meteorological calculator lets you plug in values and find a result t Conversions OF x Relative Humidity from deg F Temperature 72 deg F faz Dewpoint deg F Actual Pressure f 011 mb Relative Humidity 40 3 cateo 2w Simply choose the conversion you want at the top enter the values in the center panel t
103. ical Organization WMO a United Nations organization based in Geneva that facilitates international cooperation in meteorology and hydrology In 1961 the WMO developed the concept of the World Weather Watch WWW whose goal is to keep the entire atmosphere under continuous surveillance The nuts and bolts of the WWW are laid out in its Global Observation System GOS and data is used reprocessed and shared according to the WWW Global Data Processing System GDPS However the technical breakthrough that makes this all possible is the Global Telecommunications System GTS This is a permanent communications network that facilitates the flow of global weather information The GTS s main link is the Main Telecommunications Network MTN which links Melbourne Moscow and Washington Connected to the MTN is a series of regional networks known as Regional Meteorological Telecommunications Networks RMTNs located at Algiers Beijing Bracknell Brasilia Buenos Aires Cairo Dakar Jeddah Maracay Venezuela Nairobi New Delhi Norrkoping Sweden Offenbach Prague Rome Sofia Tokyo Toulouse France and Wellington Within each country is its own National Meteorological Telecommunications Network NMTN There are also specialized networks connected to the GTS such as the U S Air Force s Global Weather Intercept Program which uses powerful receivers to collect and share weather data from politically and economically isolated regions The we
104. ified point on your map You can also load or save a point plot list Add cities Overlays predefined city marks and labels onto your map as a reference Very important Before you can use this successfully you will need to define the cities you want drawn by editing the file DIGATMOS CIT with any text editor such as Windows Notepad The columns used are as follows 2 Latitude of city in degrees 4 Latitude of city in minutes N or S latitude sign 9 Longitude of city in degrees 10 11 Longitude of city in minutes 12 E or W longitude sign 4 14 33 Name of city as you want it to appear 2 We The DIGATMOS CIT file contains some default cities that are formatted per the above specifications which you may find useful to refer to as a template when adding new cities Page 27 Digital Atmosphere 7 18 7 19 7 20 7 21 7 22 Page 28 Add counties Overlays United States counties parishes and certain city border information After this is done the basic geography is re overlaid onto your map The source file is highly detailed condensed from U S Geological Survey data and has an accuracy of 1 mile There are about 175 000 points in this file so it may takea few minutes to plot on slower computers Outlines Overlays the actual county lines onto the map This data is in binary format and is not editable Names Overlays the names of the counties The names are truncated according to the zoom fac
105. in mountainous areas Avoid using the advection derivative to forecast Q vector movement since the field is constantly changing and may not be representative after a few hours Flow modifiers If any of these items are checkmarked it is a flag to Digital Atmosphere that it must compute divergence or vorticity and show you these results instead If a flow derivative is flagged and you pick a primary field that is a vector observed wind geostrophic wind ageostrophic wind or Q vectors the results will be valid for that particular vector field If a flow derivative option is selected and you pick a scalar variable temperature etc as your primary field only the observed winds are used in the equation and the result is multiplied by the scalar field that you select The end result is a scalar variable which can be displayed verbatim or analyzed further with the advection modifier Some useful examples of using flow modifiers are Moisture convergence Check Divergence and click on Mixing Ratio 500 mb vorticity Check Vorticity and click on Observed Wind or Geostrophic Wind Thermal advection Check the Advection selection then click on Potential Temperature 500 mb vorticity advection Check Advection and Absolute Vorticity then click on Wind Grid Moisture flux convergence Check Advection and Divergence then click on Mixing Ratio Divergence Divergence is a measure of the amount of stretching of a parcel of
106. ine and may ask that you purchase a dedicated connection at a higher fee Meteorological General Meteorological Preferences Also see the special topics on Units FOUS data level Parcel lift calculations and Physical constants I Geopotential heights in full meters only IV Round synoptic reports to nearest 3 hours when importing IV View NEXRAD RCM rather t P radar data Y Round AIREP reports within 25 mb of a standard level Y Omit highs and lows when plotting ASUS1 frontal bulletin Geopotential heights in full meters only The geopotential height on upper level charts are commonly plotted in decameters dam When this box is checked contour labels and upper plot models will appear in full meters When it is unchecked the labels and plot models will switch to conventional shortening typically used by meteorologists see table below The Digital Atmosphere 15 3 2 default setting is unchecked Level Three digit conventional shortening 100 to 500 mb Hundreds tens and units of decameters 501 to 1000 mb Hundreds tens and units of meters Round synoptic reports to nearest 3 hours when importing You have two options when importing synoptic SYNOP data you can either round the reports to the nearest 3 hours making maximum use of off hour data or use no rounding ensuring sampling of the atmosphere at an exact moment It is generally best to use no rounding when possible View NEXRAD RCM rather than RAREP radar d
107. ing a new map when maximized Thanks to Robert Dale VARIOUS ISSUES STILL TO BE RESOLVED Bitmap image not valid will still appear when viewing EMWIN products this is because the functionality has been temporarily disabled geostrophic wind field feathers not available SKEW T CAPE and other extended analysis stuff has not been restored yet will not import a V2 2 map Data Warning causes Illegal function error hidden toolbars reappear at startup this is not a bug but an item suggested and will be evaluated unusually high heights above 580 dam such as with what we are seeing this summer are inverted to 480 dam OTHER NOTES I am on the lookout for errors where a data directory data product or error message shows a path with two solidii for example c program_files digatm data or c digatm data infile txt This has Page 103 Digital Atmosphere Page 104 cropped up a couple of times but I haven t found the source of it It will cause non found datafile errors and so forth CHANGES FOR V2 2 to V2 3 BETA INITIAL JUNE 1999 Multiple chart forms eliminated This was performed to simplify numerous algorithms within Digital Atmosphere reduce the complexity of our source code and enable further development of other key areas of the program The vast majority of users indicated that they preferred one map at a time Status panel deleted and toolbars added It was decided that the status panel which has always bee
108. ions showing the actual observed conditions at that location Plotting them in Digital Atmosphere is a snap Just click on Data gt Data plots Instantly the map is filled with a smorgasbord of information Take a look at the plot in eastern Iowa It shows a temperature of 19 degrees a dewpoint of 15 degrees and a sea level pressure of 1018 7 mb prefix it with 10 if it s below 500 9 if it s above 500 and add a decimal point between the second and third digit The squiggly line at the right is the pressure trend over the past 3 hours it was rising then steady and the change was 0 4 mb divide the number by ten The long shaft sticking southwestward is the wind direction it always sticks INTO the wind so the wind is blowing from the southwest There is one tiny barb on the shaft indicating a wind speed of 5 mph every long barb is 10 mph every short one is 5 mph And in the center circle there is no shading indicating clear skies The amount of shading is proportional to the amount of Digital Atmosphere clouds You ll also note that some stations have a square this means the observation was made by a computerized station Some stations have a red color this means bad IFR weather while some are blue which means mediocre MVFR weather The coloring is determined strictly by visibility and cloud height and is more for the use of pilots and experienced meteorologists though they can clue you in on where significant weather is happe
109. is bulletin must have been imported and found with its headers intact before it can be plotted The bulletin is usually found on Unidata servers under data surface front or a similar directory or by the bulletin header name itself A couple of links are provided in Digital Atmosphere s Internet Retrieval window Note that the presence of this bulletin does not imply that computers can be used to automatically create frontal positions These bulletins are digitized from human analysis at the National Center for Environmental Prediction and transmitted in numerical form The ability for a computer to independently analyze for fronts does not exist except perhaps in experimental form and it is a poor method for analyzing the subtleties and complexities of the atmosphere One of the reasons Digital Atmosphere was created is to help forecasters locate fronts Although this product is indeed created by humans it may be inaccurate at times due to varying experience levels among the analysts A good cautionary essay on these centralized analysis charts can be found in A Case for Detailed Surface Analysis by Doswell and Sanders at http www nssl noaa gov doswell sfcanal surface_analysis html Also the resolution of the data format is no better than about 50 miles so close in zooms will not be very accurate Making your own maps By using the Create or Append options above you can create your own frontal depiction maps To pull up the drawing commands sim
110. itles 15 OCT 200d X Cancel 7 Help The above entry results in this when a map is plotted Tf c2 65 192 68 Mis y 3 4 de Bv 10 3 65 S29 65 T 73 632 co HO amp 194 7 sh DR 15 OCT 2000 1200Z SFC STATION PLOTS tod 2 MO 7 12 Copy to clipboard This is the easiest way of transferring a workchart to another software program When you choose this the workchart is placed in the Windows clipboard From there you can paste 1t into any of your favorite graphics programs Page 25 Digital Atmosphere 7 13 Make topography Available only in registered version Renders a topographic representation terrain features of the Earth on your map projection After the topography is drawn Digital Atmosphere then re overlays the basic geography data The topography draw operation may take a few minutes on slower computers Example of topography in northern Siberia 7 14 Photoreal topography Available only in registered version Renders a photoreal representation of topography If you plan to use this feature often you may want to head to File gt Preferences gt Maps and tweak the map elements to give you the most useful possible image Page 26 Digital Atmosphere 7 15 7 16 7 17 Example of pressure field over central Africa using photoreal topography Add basemap Redraws the workchart basemap without erasing the contents of the workchart Add point Overlays a spec
111. l assistance State City Fre MHz Point of contact AL Mobile 148 375 142 375 Don Arnold Michael Redd 601 762 1812 AR Fayetteville 148 050 Dan Puckett 501 575 2905 FL Orlando 156 105 Terry Schenk 407 323 2500 FL St Petersburg 139 2125 Jack Belich 727 893 8652 IL Wheaton 148 6375 Rich Jirsa 630 682 7925 KS Wichita 1 John Crosby 316 383 7546 MD Laurel 142 925 Maryland Radio Center 301 725 1212 MD Silver Spring 400 175 Ken Bashford 301 713 0326 x 191 MI Battle Creek 150 500 Jim Zoss 616 966 3550 MI Coldwater 150 500 Jim Zoss 616 966 3550 MI Jackson 150 500 Jim Zoss 616 966 3550 MI Kalamazoo 150 500 Jim Zoss 616 966 3550 MI Sturgis 150 500 Jim Zoss 616 966 3550 MO Buffalo 139 2125 Terry James 417 345 7330 MO Kansas City 139 2125 Larry Gonnello Sr 816 274 1806 MO St Louis 460 425 Mike Redman 314 889 2362 ND Bismarck 143 150 Unknown ND Fargo 143 150 Unknown ND Grand Forks 143 150 Jim Belles 701 795 5659 NE Wilber 156 105 B J Fictum 402 826 2147 OK Atoka 153 950 Eddie Cooke 405 889 7321 OK Durant 150 750 Johnny Shepard 405 924 3661 OK Enid 142 950 Mike Honigsberg 405 249 5969 OK Guymon 150 750 Bill Wyatt OK Kiamichi Mtn 142 950 Keith Butterfield 918 669 7388 OK McAlester 148 775 Ralph Suter 918 426 0141 OK Miami 150 750 Terry Durborow 918 542 7133 OK Norman 169 025 Ken Brown 405 366 6587 OK Oklahoma City 150 750 Ron Hill 40
112. le Tables as many times as you wish SPECIAL NOTE Effective with Digital Atmosphere V2 2 a new station table format is being used which Digital Atmosphere contains changes in columns and data fields Never try to import older DIGATMOS STN formats as you will corrupt your installed copy 6 14 Preferences This section has a chapter of its own Please consult the detailed chapter on Preferences Settings 6 15 Exit Exits Digital Atmosphere The background map will be saved and it will automatically appear the next time you run the program The last data set you imported will continue to be available Page 19 Digital Atmosphere 7 2 7 3 Page 20 Map Commands Introduction These commands are used to generate maps for Digital Atmosphere Erase map Before you make annotations plots or contours on your map Digital Atmosphere retains a copy of the original map image in case you want to start with a blank slate Use this command whenever you want to erase weather data from the map Generate map There are three ways to generate a new map from scratch e Map gt Generate Map gt Enter lat long e Map gt Generate Map gt Enter station e Generate Map list of countries and regions on the Speed Buttons toolbar The easiest method is to use the Generate map dropdown box on the speed button toolbar and pick a country or continent For those that want more accuracy these two selections will provide greater
113. lect this option Note that gradient fills only work with scalar fields not vector fields Automatic smoothing If checked Digital Atmosphere will automatically determine the surface and upper air surface radius based on existing data for the Weighted Cressman and Barnes analyses Figure geostrophic heights When analyzing upper level heights Digital Atmosphere will calculate the height field by computing contour gradients at each station derived from the wind direction speed and existing height This takes longer but yields much more accurate results You may uncheck this if you wish to perform only a very quick rough height analysis Digital Atmosphere 500 mb heights WITHOUT geostrophic heights Note that the wind directions are largely ignored and the analysis looks coarser 500 mb heights WITH geostrophic heights Wind directions are used to estimate the geostrophic height field yielding a better looking map 15 6 2 Isopleths lsopleths Small fonts IV Negative fonts FF Transparent fonts Page 69 Digital Atmosphere 15 6 3 Page 70 This option simply controls what size and type of fonts are used to label contour lines on analysis charts Transparent controls whether the map below bleeds through the font A sample analysis with small fonts checked and negative fonts checked AKi _ NP J The Same thing except with small fonts unchecked and negative fonts unch
114. m data plots Page 35 Digital Atmosphere 9 2 Page 36 Analysis Commands Introduction Digital Atmosphere hosts a powerful suite of tools for analyzing various atmospheric properties It is quite simple to use You simply click on a primary field that you want to view such as temperature wind speed pressure etc in the Analysis menu However if you first click on a derivative field i e vorticity divergence or advection in the status panel Digital Atmosphere places a checkmark next to that field Derivative fields are not analyzed until you click on a primary field from the Analysis menu Only then are the derivative choices looked at All analysis methods are computed based on whatever level is selected under the Active Level pop up menu on the status panel so if the analysis does not appear it means no data is available for the active level Font types used during analysis contouring and labelling operations are controlled in File Preferences Fonts under Annotations Only the font name is used the size is ignored Analysis basics To fully understand how the analysis routines work you have to know a little bit about the theory behind them All meteorological fields can be described as a series of waves For example assume that at a certain time the coldest spot in the country is International Falls MN at 12 F and the hottest spot is Death Valley CA at 96 F Then draw a long line on your map that passes thro
115. models see Appendix Scripting Script commands for convective outlooks and MVFR IFR depiction dy1 dy2 cig added to documentation Printing capabilities have been fully restored and diagnostic gridboxes on printouts are eliminated Print button has been fixed VERSION 2000 V1 0 12 3 00 e Option added to File gt Preferences gt Analysis to allow transparent fonts Slight changes made to remove plotting of extra pixel line at bottom of NMC fonts Errors under Win 98 with File gt Get Archived Data and EMWIN ZIS extraction fixed EMWIN ingest capabilities improved with regards to extraction of ZIS files previous versions were error prone Map gt Generate by Station fixed Option for 1000 500 mb thickness added in File gt Preferences gt Contours MVFR IFR contour labels were invisible with certain contour font combinations this is fixed VERSION 2000 beta 3 12 2 00 NEW FEATURES Page 97 Digital Atmosphere Page 98 Added EMWIN ingest engine in EMWIN gt Ingest EMWIN upper air upr added to File gt Import EMWIN data Added command to clear out data directory File gt Clear data directory Frontal workchart toolbox added in Data gt Frontal bulletins and right click menu 1000 500 mb thickness added in Analysis gt Temperature gt Thickness upper air data is required Calculator now allows station pressure wind chill and heat index calculations entirely in metric Replaced CXN CXP c
116. more than half of sky hundreds of feet OKTAS Cloud cover in oktas eighths ID ICAO Station identifier 4 letter ICAO ID WMO Station identifier 5 digit WMO PCPO1 Precipitation during past 1 hour PCP06 Precipitation during past 6 hours PCP12 Precipitation during past 12 hours PCP18 Precipitation during past 18 hours PCP24 Precipitation during past 24 hours PTEND Pictogram of pressure tendency during past 3 hours CLD L Pictogram of low cloud type CLD M Pictogram of middle cloud type Digital Atmosphere CLD H Pictogram of high cloud type CLDHGT Cloud height code synoptic only see chart below CLDAMT Cloud amount code synoptic only see chart below SHIPDIR Pictogram of direction of ship movement SHIPSPD Speed of ship movement kt SEATEMP Sea surface temperature C or F TEMPTYPE Type of temperature measurement device WAVEPD Period of ocean waves sec WAVEHGT Height of ocean waves ft or m SEAINSTHGT Instrument measured height of ocean waves ft or m WINDPD Ocean wind wave period sec WINDHGT Ocean wind wave height ft or m SWELL1DIR Direction of primary ocean swells deg SWELL2DIR Direction of secondary ocean swells deg SWELL1PD Primary ocean swell period sec SWELL1HGT Primary ocean swell height ft or m SWELL2PD Secondary ocean swell period sec SWELL2HGT Secondary ocean swell height ft or m MINTEMP Minimum temperature C or E MAXTEMP Maximum temperature C or F GRNDSTATE Ground state c
117. n File gt Preferences gt Meteorological gt Geopotential height in full meters only Geostrophic height contouring algorithms improved to eliminate irregularities along margins Added upper highs lows Added tutorial directory with tutorial files Re instated and improved serial key routines VERSION 2000 beta 1 11 11 00 Added photorealistic topography Fixed zoom bar on map settings panel not working Added file drag and drop capability from Windows Explorer Fixed outer space fill Fixed Quit Searching in Climatology graph Added NCEP legacy fonts to isoplething routines for labelling of lines Added Thick Contours option in File gt Preferences gt Analysis makes isopleths twice as wide Added easter egg Shift Ctrl F7 Changed FTP timeout from 1000 to 15 seconds so a quicker response occurs if a connection is hung Vastly improved isentropic analysis in Level dropdown on toolbar Added freeform horizontal analysis in Level dropdown on toolbar Corrected and improved 3 D atmosphere build in Analysis menu Reinstated and improved roaming sounding Satellite wind observation import provided Slight bug in contouring fixed prevented random charts from drawing any contour lines Changed Wind Speed analysis so that it uses a gridded x y wind field for better accuracy Documentation provided in dual formats context sensitive Windows Help and PDF format Numerous additions edits and improvements to help documentation Ad
118. n a part of Digital Atmosphere was too awkward cluttered and frequently got in the way It has been replaced by two toolbars a time toolbar and a wind toolbar They can be hidden or displayed in the View dropdown menu Tab ordering improved The tabbing order of controls in the map customization screens were improved so that navigation without the mouse would be much easier Automated version numbering This is mostly an internal change that isn t of interest to most users Version and build numbers listed on the Splash Screen and About Screen are now extracted directly from the application file This is the same data seen when you choose Properties and Version from Windows Explorer A new registration authentication scheme has been enabled To register your copy you will need to go to Help Register to find out their individual serial number then contact us for a key number Note that this keying scheme is subject to change RCM NEXRAD radar parsing has been vastly improved The algorithms were edited tested and tweaked to give a high level of competency in parsing NEXRAD RCM data Furthermore the algorithms extract cell mesocyclone TVS hail and wind data from the datasets RCM data is not available at most weather data servers but it can be found in the SAORCMUS TXT file regularly transmitted by EMWIN this is also available at http emwin cira colostate edu rxfiles SAORCMUS TXT which has been placed in the new Internet dat
119. n a script in run time Go to the scripts toolbar and select the Run Script button To run a script at startup Advanced users can run scripts on Digital Atmosphere startup by using standard command line parameters A space and the full name of the script file is simply appended after the filename at the command prompt or in the shortcut property for Digital Atmosphere To use the scheduler Go to the scripts toolbar and select the Scheduler button it will say Scheduler on or Scheduler off This will bring up a configuration window see below where the scheduler will coordinate which script files run at which time e You must set Enable scheduler for the scheduler to take effect e When the scheduler is no longer wanted bring up this window again and unset Enable scheduler e To specify the execution time for each script write the execution time in 4 digit UTC time in hhmm format i e 7 45 am is 0745 and 2 15 pm is 1415 followed by a space and the name of the file including its dsf extension Be sure to specify the full pathname of the file otherwise Digital Atmosphere will assume it is located in your Digital Atmosphere directory e There can be an unlimited number of scripts and execution times in this list e Advanced users You can edit or swap out this schedule list if you wish it s located in the Digital Atmosphere directory under digatmos stft Page 81 Digital Atmosphere Page 82 t Script Timer
120. n for map display x Enter the ICAO IATA station number or partial station name Station names must be greater than 6 characters lt TOP Map width miles Map size pixels 2300 540 x aso x cs If you know the station that you want to center you map on you can simply enter it here e Station Enter an ICAO code WMO code IATA code or partial station name e Map width Sets the width of the map in miles e Map size Allows you to specify how many screen pixels wide and tall you want the map image to be You may also wish to choose one of the map size quick pick buttons If you want an exceptionally detailed image you may want to choose one of the higher settings The 1550 x 1150 size yields excellent printed maps that are suitable for publishing If this image size is larger than the screen you will be provided with scroll bars to roam around the image However note that large maps place a burden on your computer s resources and too many large maps open at the same time may cause warnings or errors Avoid setting sizes larger than 2000 pixels as there may not be enough memory Load map Loads a workchart from your disk drive You will need a previously saved workchart which can be saved using the Save Map command Technical tips Load Map loads images that are Windows bitmaps filename BMP and it also expects to load a map Digital Atmosphere tot 7 8 attribute file with the same name ATR which cont
121. n the tree shows an incorrect or blank full length breakout you can fix it by editing the file DIGATMOS EMR in your Digital Atmosphere directory Likewise incorrect or missing product breakouts can be edited in DIGATMOS EMP Having missing or incorrect breakouts has no impact on the functionality of Digital Atmosphere Display image Displays any graphic image in the EMWIN data directory as specified by File gt Preferences gt General gt EMWIN Data Directory Digital Atmosphere 12 12 1 12 2 12 3 Climatology Menu Commands Extract data If you want to plot or analyze climatological data this is where to start Extract Data will allow you to select a category and timeframe of climatological data Digital Atmosphere will then create a custom data field saving it into CUSTOM DAT in your Digital Atmosphere directory This can then be immediately plotted with Graphics Plot Custom Data or analyzed with Analyze Custom Data Field You can even import the data into a spreadsheet or database program Graph This option will let you graph the climatology for any of 2 000 stations around the world Simply enter a partial word or country digraph to search for a station or choose from the drop down list What you ll see is a graph of average high and low temperatures for each month as well as extreme high and low temperatures for each month They will be indicated in either degrees Fahrenheit or Celsius depending on your
122. nd check the Autosave box The graphics type is determined by the extension of your filename BMP JPG PNG PCX or TIF Every time the map is refreshed automatically the completed map will be exported to your target file Previous versions of Digital Atmosphere had trouble identifying some warnings This occurred when warning bulletins did not end with the NNNN termination sequence this recently began appearing on EMWIN therefore warnings piled up in the first warning text slot This has been fixed a new header now can substitute for an NNNN termination sequence CHANGES FOR V2 1C BETA to V2 2 FEBRUARY 1999 Preferences buttons for the FOUS level have been added This is located in Preferences Meteorological This allows a level aloft such as the T3 and T5 and R2 and R3 levels to be plotted or analyzed Note that since the T3 R2 and T5 R3 levels aren t exactly the same you should avoid calculations which cause the temperature and relative humidity to be combined for example dewpoint analyses Preferences buttons for the default time select have been added It is located in Preferences General Using these buttons you can pick something else besides Automatic time select to appear on the status panel Page 105 Digital Atmosphere Page 106 when Digital Atmosphere is started Cursor lat long can be determined by right clicking the map Using the pop up menu simply choose Cursor location and an information box
123. nd grid tmf Temperature deg F tmc Temperature deg C pot Potential temperature deg K WCX Wind chill factor hix Heat index dwf Dewpoint deg F dwc Dewpoint deg C rhu Relative humidity mxr Mixing ratio eqp Equivalent potential temperature theta e slp Sea level pressure alt Altimeter setting QNH wsp Wind speed cig Ceiling hgt Geopotential height thk Thickness 1000 500 mb wrx Warning overlays pot 1 hour precipitation p06 6 hour precipitation p12 12 hour precipitation p18 18 hour precipitation p24 24 hour precipitation rst RCM radar storm centroids rhl RCM radar hail signatures rms RCM centroid movement and speed rtv RCM tornado TVS signature reh RCM echo height signatures rem RCM echo movement wxp ASUS1 KWBC frontal depiction bulletin ste Sea surface temperature pdw Wave period htw Wave height hti Wave instrument measured height pdd Wind wave period htd Wind wave height di1 Primary swell direction di2 Secondary swell direction pd Primary swell period htl Primary swell height Page 85 Digital Atmosphere 17 4 Page 86 pd2 Secondary swell period ht2 Secondary swell height cig MVFR IFR weather dy1 SPC Convective Outlook Day 1 dy2 SPC Convective Outlook Day 2 06k Surface 6000 ft shear not completed lcl Lifted condensation level not completed be CAPE not completed be CIN not completed CXX not used hux not used iht not used zb not used prt not u
124. nges Note that longitude in the west hemisphere is negative files imported from WeatherGraphix will need to have the longitude signs inverted The color of the line is controlled by the roads and custom lines setting in Preferences Map Contour labelling algorithm improved Previous versions of Digital Atmosphere plotted isopleth labels only at the chart edges making closed contours difficult to interpret Digital Atmosphere will now plot labels in many closed contour patterns Data tables now produced These are stored in OUTPUT SFC surface and OUTPUT UPR upper every time you import data These tables can be parsed using your own applications or can be brought into spreadsheets and databases Precipitation data now available Data from the synoptic 6xxxx group is now imported into Digital Atmosphere and can be plotted or contoured Note that most U S and Canada stations report 6 hour precipitation Precipitation inches millimeters choice added in Preferences Meteorological This applies to precipitation plots and contours Pressure tendency and low middle and high cloud symbols have been added These can be plotted if they are part of the surface plot in Preferences Station Plots The pressure tendency can be analyzed and contoured Maps can be automatically exported when the program is in automatic mode You simply specify the target file in Preferences General under Autosave a complete directory and filename is required a
125. ning If you look in the southeast U S you ll see that some stations have two fat dots This is the international symbol for rain Overlaying more contours Now choose Analysis gt Pressure Height gt Sea level pressure Nice You just added the same field seen earlier on top of the map This illustrates how you can view different meteorological fields at the same time Seeing the wind flow It is possible to visualize the wind field Go ahead and click on Map gt Erase map Now choose Analysis gt Wind gt Wind field You ll see a pretty cool gridded array of wind patterns It s the ideal thing to depict how the air is moving Another way to see the winds A second way of seeing winds is to choose streamlines Go ahead and choose Map gt Erase map again Now choose Analysis gt Wind gt Streamlines These lines are always oriented parallel with the wind You can see that if you released a balloon in Kansas and it stayed near the ground it would probably drift towards Michigan Forecasters in the tropics love to use streamlines as it s one of the best tools for finding disturbances in that region of the world Looking at isotherms Remember how you overlaid isobars on the map It s easy to overlay other fields such as isotherms lines of equal temperature Just go to Analyze gt Temperature gt Temperature F or C Moving around Want to look at a different part of the world Look at the speed button toolbar and at the far right
126. noptic header in addition to SA and SM when determining times for synoptic reports Thanks to Hans Stefan Lichius Preferences gt Meteorological option for Round synoptic reports to nearest 6 hours when importing has been corrected to round to nearest 3 hours Rounding operations have always been to nearest 3 hours Data gt Warnings has been adjusted to import warning datasets correctly EMWIN users who keep seeing outdated warnings on their maps should change the purge intervals in their EMWIN reception software The option Default data time selection in File gt Preferences gt General is now functional again BUILD 885 8 16 99 If main window is maximized the window is no longer resized when a new chart is loaded Emwin Scheduler on receipt of new EMWIN data the map did not erase this has been fixed MVFR IFR contour analysis has been fixed An Access Violation that popped up during import of some RCM NEXRAD datasets was fixed by adding code to quality check incoming data Thanks in part to Wayne Cotterly Some problems with precipitation contouring in synoptic reports was fixed additional code was written so that Digital Atmosphere could differentiate missing reports from zero and zero from nonzero amounts Thanks to Hans Stefan Lichius In an effort to consolidate internal data processing upper air split files OUTPUT HOO H85 F18 etc are no longer used This will solve QC problems where R
127. ntral longitude degrees real Zoom setting 3963 z where z map width in miles integer Not used integer Not used integer Not used integer Not used integer Map height pixels integer Map width pixels integer Offset x direction pixels integer Offset y direction pixels Real types have the range 2 9 x 10 39 1 7 x 1038 with 11 12 significant bits and a length of 6 bytes Integer types have the range 2147483648 2147483647 and are signed 32 bit 4 byte little endian Digital Atmosphere 17 3 Scripting Scripting is a powerful function that allows Digital Atmosphere to do various tasks while unattended You can have it download data every half hour and always have the latest map displayed or send charts to the printer automatically The possibilities are up to you SCRIPTING BASICS To run a single script command Simply type in the script command in the command line on the scripts toolbar Hit return or click Enter and it will be processed Note that this does not run a script it just runs a script command A list of commands is below To write a script Use any text editor or click on Create Script on the scripts toolbar and you can begin typing your script Note that scripts should use the file extension dsf in order to be properly recognized in Digital Atmosphere To comment out a line of code simply place a semicolon at the beginning of the line Commands are generally not case sensitive To ru
128. o called hourly radar reports RAREPS and SD reports Early versions of Digital Atmosphere do not import this type of data Radar reports come from about 100 stations around the country A few years ago they were typed up by humans but most of them are now centrally generated by computer based on images from NEXRAD radar sites around the country This is what a radar report looks like MCI 0225 CELLS TRW NEW 250 195 D10 C2330 MT 300 Digital Atmosphere OI22 FD winds aloft data This is not an analysis of real conditions rather it is numerical output from the National Centers for Environmental Prediction formerly NMC in Washington DC It is used primarily for aviation forecasting purposes consisting of a coded wind and temperature forecast at 12 and 24 hours into the future Nevertheless it makes excellent forecasting charts in Digital Atmosphere For Hours ID Use Z From Now 3000 6000 9000 12000 18000 24000 2XG 09 18 00 09 3613 2911 06 2520 02 2430 03 2342 15 2462 26 Rawinsonde data Also called TTAA data This is the backbone of upper air observation reports sent twice daily from hundreds of stations worldwide several dozen in the United States alone It is a highly numerical coded set of data that is used extensively in meteorological operations and is used as input into the numerical forecast models Here s an example of what it looks like 72558 TTAA 69121 72558 99973 00821 30002 001
129. ode see below Ground state codes N 0 Du BUD CO Surface of ground dry without cracks and no appreciable amount of dust or loose sand Surface of ground moist Surface of ground wet Flooded Surface of ground frozen Glaze on ground Loose dry dust or sand not covering ground completely Thin cover of loose dry dust or sand covering ground completely Moderate or thick cover of loose dry dust or sand covering ground completely Extremely dry with cracks Ground predominantly covered by ice Compact or wet snow with or without ice covering less than half of ground Compact or wet snow with or without ice covering half to less than entire ground Even layer of compact or wet snow covering ground completely Uneven layer of compact or wet snow covering ground completely Loose dry snow covering less than half of ground Loose dry snow covering at least half of ground but ground not completely covered Even layer of loose dry snow covering ground completely Uneven layer of loose dry snow covering ground completely Snow covering ground completely deep drifts Synoptic cloud amount codes CLDAMT Nh Page 65 Digital Atmosphere 15 5 3 Page 66 This category is defined as Nh the amount of all the low cloud present or if no low cloud is present the amount of all the middle clouds present The figure is always in oktas eighths 9 is reserved for sky obscured by fog and or other meteorological phenomena and is reserved for
130. open a connection to the Internet using your Dial Up Networking or Remote Access Services to connect to your Internet service provider If you are new to using the Internet and need some basic information see the section on getting data at the end of this manual We ve provided some pointers for you Retrieve data This module retrieves alphanumeric data through the Internet and saves it to your hard drive When the data download is completely finished Digital Atmosphere will import the data for you This means you can immediately begin plotting and analyzing To use Retrieve Data you must first open a connection to the Internet through your service provider before this command will work Note that you must have a standard Winsock Internet connection Firewalls or unusual configurations could cause problems If you have a proxy server you may want to enter your proxy host information in Preferences gt Misc When you select Retrieve data you will be presented with a dialog box containing a list where you can check off the items you want to download see illustration from a product list Once you press Retrieve the chosen products will be downloaded and stored in your data directory Then you can use File Import Directory to see the results Since Internet sites often change you can fully edit the list of products and data directly from this dialog box by highlighting the item you wish to change and clicking the Edit Site button or the Del
131. or MasterCard and E mail us at support weathergraphics com Include the expiration date and cardholder name your address and phone number Orders are usually processed within 24 hours e Fax Fax your order to 405 329 5275 For your convenience there s a file in your Digital Atmosphere directory called ORDER TXT which you can print out and send to us Orders will usually be processed within 24 hours Postal mail Orders may be sent to Weather Graphics Technologies P O Box 450211 Garland Texas 75045 0211 USA Orders will be processed upon receipt Weatherdish users Do you use Weatherdish If so you can register by contacting the friendly folks at ItWorks 3490 Silverbell Rd Chico CA 95973 530 899 8434 E mail info weatherdish com or www weatherdish com e Weather conference We often attend severe weather conventions where you can register your copy Page 5 Digital Atmosphere Page 6 Tutorial Tutorial on Digital Atmosphere Now we present a quick tutorial to help you get up and running You may want to print out this help page and follow along if you re in Windows Help just go to File gt Print Topic to print this page Loading a little data Digital Atmosphere comes with a set of prepackaged data for November 18 2000 To load this data just choose File gt Import a File and select the folder tutorial Select the file incoming txt Digital Atmosphere will import all the data in this file On a Penti
132. ortant documents and desktop publishing Compresed TIF saving Page 23 Digital Atmosphere is not available since this requires separate licensing from Unisys Save As File name Save as type PNG Portable Network Graphic Cancel The illustration above shows where you change the image type when using Export Map If you have chosen Save Map all you will see is BMP 7 9 Blank map Creates a workchart with no background map Projection data from the last workchart is used 7 10 Information Displays detailed information about the map currently shown Included is the map width and height in both pixels and nautical miles the center latitude longitude of the map and the corner latitude longitude points All negative latitudes indicate the southern hemisphere and all negative longitudes indicate the western hemisphere Page 24 Digital Atmosphere Information x A Map width x height y 640 x 480 pixels 2952 5 x 2183 5 nm Projection Orthographic Coordinates lat long Center 39 07 95 63 Top left 51 31 137 40 Top right 51 31 53 87 Bottom left 17 20 121 47 Bottom right 17 20 69 79 te 7 11 Set comment Sets an annotation that will be prefixed to the legend of a workchart when data or contours are drawn You can enter any information you want A typical purpose is for specifying exact dates Enter comment x Add a comment to be appended to chart t
133. ounty name label file with editable CXT file Moved county name label for Ventura County California westward slightly Added aspect ratio to Map gt Generate Map Color palettes in Preferences gt Colors are now saved and loaded with maps with ATP file Added more information in help file Added Dutch weather station corrections in DIGATMOS STN Drop a file from Windows explorer onto a running copy of Digital Atmosphere to import that file When a convective outlook indicates NO TSTMS this is plotted on the map Print capability re enabled was disabled during beta tests ERROR FIXES Error File not found error in File gt Get Archive Data FIXED Error Old links for UNCA in DIGATMOS SLZ Internet retrieval table FIXED Error Altimeter setting H L values round to nearest inch FIXED Error Map gt Generate Map offset settings may produce bad results FIXED Error If edge of Earth is seen in a generated map ocean fills do not work correctly FIXED Error DRSN drifting snow in METAR not properly recognized by Dig Atm FIXED Error Help does not work for Map gt Information button FIXED Error Map gt Information produces some bad results FIXED Error QC rubberband keeps appearing erratically FIXED NOW DISAPPEARS ON RELEASE OF MOUSECLICK Error When cancelling in Map gt Generate map corrupt results occur FIXED COULD NOT DUPLICATE Fronts are inconsistently erased COULD NOT DUPLICATE Climatology contour o
134. permanent e Ignore Changes Ignores any changes that you ve made to the report and moves to the next one e Delete Report If the individual report is so corrupted that you know you won t want to use it you ll probably want to delete it This is the button to use e Stop Search Stops sifting through the file saving any values that you ve already entered Note that QC displays all data within the bounding box even if it s filtered out on the map so you may need to press Accept entry numerous times until you find the station you want One way of avoiding this problem is to make the initial QC box as small as possible so that you get only the station you want Since QC changes the formatted binary data files you will lose your changes if you re import the original data Page 15 Digital Atmosphere 6 9 6 10 Page 16 View raw data Very often you will want to go back and look at the original data Not only is this handy it is recommended so that you can review observations for vital clues such as observer remarks as well as look through any forecast data you might have captured The file that is shown is the internally saved clean data file produced by the most recent File Import command The original raw data file is not referenced and does not have to be present If you don t like this interface you can view the same data file using any text editor and setting it to examine DATA USR in your Digital Atmo
135. played in the time token panel Solving incorrect time problems If the time tokens always show a slightly incorrect hour check your Preferences menu under the General tab and make sure the Daylight Saving checkbox is marked in accordance with whether daylight savings time is in effect If the hours are significantly off go to your Windows control panel look under Date Time and make sure your computer is set to the correct time zone Then make sure your system clock is set to a current time which is valid for that time zone For example if you live in New York and typically have your computer clock set to Greenwich Mean Time you will have to set the Windows time zone to GMT rather than Eastern Time Solving access problems Digital Atmosphere must have access to a true Winsock Internet connection in order to retrieve data It may not work with proprietary systems such as AOL and MSN If for some reason you can t retrieve data through Digital Atmosphere all is not lost You can still use your Internet browser to get products then save them to your Digital Atmosphere data directory which is most users have had to do up until 1997 Technical tip Do you want to swap data product lists with other users No problem we ve made it easy Simply give them a copy of your DIGATMOS SLZ file it s in your Digital Atmosphere directory If they replace their DIGATMOS SLZ file with yours they ll get your list of data products We sometimes offer updated
136. ply right click on the map and choose frontal depiction tools You will see a menu like the one below Identify warning Get lat long Show sounding Erase markings Aaa Add front point Set cold front Set warm front Set occluded front Set stationary front Set trough Add high Add low Drawing a front So that the barbs point the correct way as you draw the line cold air must always be on your right side except when drawing warm fronts the easiest way to remember this rule is to always start from the center of a low pressure area and work your way to higher pressure Simply set the cursor on the first point choose Set xxx front then move along the front and right click Frontal depiction tools gt Add front point at each point to define 3 or more points along the front The front will be drawn as you go along and will be smoothed automatically as a spline Drawing highs and lows Simply right click on the map and choose Frontal Depiction Tools gt Add high low to mark the position of a high or low pressure area You will be prompted for a central pressure in millibars You can leave this blank if you wish not to specify one Special notes Please note that due to inherent limitations in the ASUS1 KWBC format which is what Digital Atmosphere adheres to precision of the toolbox commands is limited to 60 miles 100 km or more Therefore you cannot draw microscale fronts and extremely small scale outflow bo
137. ras are there If you order the CD ROM version an extra 10 plus 5 shipping you get a copy of NSSFC 5 Operational Mesoanalysis a 42 meg PDF document on small scale forecasting We also hope that our low price and our commitment to continued development work is an incentive to register We prefer to offer affordable prices and great service rather than inflated markups and shoddy support which is common in the software industry Your registration is greatly appreciated UPGRADE INFORMATION registered users only Old key numbers from previous versions will not work in Digital Atmosphere 2000 Digital Atmosphere 2000 is the first major upgrade since 1997 and a 45 fee will apply to all registered users who want to upgrade their copy of Digital Atmosphere Of course our upgrade policy has always been quite generous and we have released dozens of free upgrades to Digital Atmosphere during the past few years However the weather software market is not very large and we have to periodically recover costs to continue further development work If you choose not to upgrade you can always reinstall your old version and continue to use it REGISTRATION PRICING e First time users Welcome The cost of Digital Atmosphere is 68 You ll be added to our books as a registered user e Registered Digital Atmosphere users V1 x V2 x The upgrade cost is 45 You will need to specify in your order that you are upgrading and you will need to provide your
138. re calculated Valid settings are as follows Digital Atmosphere 15 3 5 e Surface based parcel A parcel is lifted from the surface e Lowest 100 mb A parcel takes on the average mixing ratio and potential temperature within the lowest 100 mb before being lifted most representative of a convective atmosphere at the time of the sounding e Lowest 150 mb A parcel takes on the average mixing ratio and potential temperature within the lowest 150 mb before being lifted e Best layer A parcel takes on the highest theta E the level where mixing ratio and potential temperature are the highest within the lowest 150 mb of the atmosphere Physical constants Lowest possible METAR pressure feso mb Reset Rotation constant fo 00007282 sec Reset Gravity constant fa 806 misec sec Reset Lowest possible METAR pressure The METAR surface observation code format only allows the tens units and tenths place to be encoded which means that Digital Atmosphere has to determine whether the final millibar value is 9xx x or 10xx x The default value for lowest METAR pressure is 960 mb which means that if a value such as 584 is found Digital Atmosphere will assume it is 1058 4 mb not 958 4 mb Normally there is no need to change this but if you re looking at exceptionally low pressure areas and the sea level pressure contours aren t plotting correctly you ll want to decrease this value Likewise if you re looking at very high pressure an
139. rman Oklahoma These are centralized human produced forecasts issued several times a day and are used to help provide guidance to National Weather Service forecast offices They are also used frequently by storm chasers pilots and hobbyists To use this option you must have imported a convective outlook as part of your raw data set or from one of the choices in Internet gt Retrieve data Advanced users can modify the color scheme by changing the contents of the file DIGATMOS CCC in the Digital Atmosphere directory using a standard text editor such as Notepad never use a word processor such as Microsoft Word or you will corrupt the file This file contains self explanatory instructions for modifying the hexadecimal numbers used to determine colors of the various threat boundaries If there are any problems ingesting a bulletin the problem is most likely an error in the composition of the bulletin It is not necessary for the header to be intact but the STORM PREDICTION CENTER title must appear in the bulletin along with the convective outlook type valid times and standard bounding locations of Page 33 Digital Atmosphere Page 34 each threat area Appearance of a convective outlook plot The raw data appears as follows 492 ACUS2 KMKC 041803 SWODY MKC AC 041801 2
140. rted as usual from the data directory or from a specified file The rules for this data are e Comma delimited data only e Each line must correspond to one observation e No extraneous commas are permitted even within quote marks e The observation must contain the station s latitude and longitude To take advantage of this capability you need to open the DIGATMOS FMT file with a text editor and define the start sequence and the parameters that apply to that type of data Start sequence You define the start sequence by placing a start sequence between brackets in the DIGATMOS FMT file for example if your database starts out with Joe s Data you should start out with this Joe s Data No database entries are read in until the start sequence is found Parameter list To actually read the data you will need to create a parameter list such as this TMP 4 DWP 6 Each entry must be on its own line and the list ends when the end of the file is reached or another start sequence is found The example above indicates that the temperature can be found in column 4 and the dewpoint can be found in column 6 Sample listing Here is a sample of an entry in DIGATMOS FMT which is used for Australian Bureau of Meteorology AXF data synopData ICA 3 WMO 1 LAT 6 LON 7 ELE 9 TIM 5 DAT 4 TMP 22 DWP 23 WND 11 WNM 12 SKY 10 CIG 26 WXX 14 Page 87 Digital Atmosphere 17 5 Page 88 VIS 13 Valid parameters ICA xxx I
141. rth Users need to be within 30 60 miles of the station If you re within range EMWIN software on your PC usually Maryland Radio Center s Weathernode running under Windows receives the signal from the demodulator stores the received weather products onto disk and allows you to display this information WHAT YOU NEED All you need is a cheap police scanner even a handheld one a 100 DM 201B demodulator plug and a personal computer with a spare COM port WHAT S IN IT FOR YOU Since this is a standard radio broadcast hardware requirements are minimal and will save you money A small antenna is all that is needed meaning that many apartment dwellers won t need any outdoor antenna As with the satellite broadcast there are no fees to get the data THE PITFALLS Aside from private and local government efforts the only federally funded rebroadcasts are in the Washington DC and Norman OK areas No plans are in effect to implement government funded EMWIN rebroadcasts nationwide All other rebroadcasts that exist are the result of cooperative efforts by public and private agencies downlinking from the various satellites and then rebroadcasting the datastream Another drawback is that the datastream is usually a slow 1200 baud reducing the number of products you can receive Some of these broadcasts are possibly experimental and could be withdrawn or discontinued at any time Where to get equipment and software Maryland Radio Center Inc
142. s Panel under active level You will be prompted for a level in whole Kelvin degrees While this level is active all analysis operations will pertain to parameters on that particular isentropic surface The two most useful parameters under Analysis are isentropic height and wind grid Digital Atmosphere Isentropic height has been added as an Analysis option This analyzes the height of datapoints in mb at the Active Level Therefore its only suggested use is when an isentropic level has been entered into the Status Panel Its color scheme currently follows the 500 mb contour scheme A Composed CAPE option has been added in Analysis This builds a 3 dimensional representation of the atmosphere based on existing observations and calculates CAPE at each gridpoint rather than calculating CAPE at each station CAPE LCL and 0 6 km mean wind are now functional and can be accessed under the Analysis menu A bug has been fixed where the toolbar Print button had no effect A bug has been fixed where analysis gradient fills with no isopleths produced no background map CHANGES FOR V2 1 to V2 1A BETA JANUARY 1999 Documentation is now contained entirely in an Adobe Acrobat document The manual was extensively rewritten and updated Lat long grid usage is now controlled by the Preferences Color checkbox The none radio button under lat long grid has been removed New time tokens for Internet data products have been introd
143. sed SAMPLE SCRIPTS This script downloads synoptic data from Albany imports it displays plots and sea level pressure and outputs it to a file Note that this will probably not work on your computer without changes and is only intended to demonstrate the appearance of script commands download http www atmos albany edu weather data1 surface synn Y M D S_syn wmo c digatm data t est dat import c digatm data product plf 0 Test plot product slp 0 Test plot export d da20 bin map out jpg This script plots a series of upper air charts for 1200 UTC August 27 1990 from our Upper Archives CD ROM and saves the completed charts for 250 mb 500 mb 700 mb and 850 mb to individual files 1990082712250 gif etc Again this may not work on your computer without some changes set 1 9008 set 2 90082712 archive f 1 2 product plf 250 PLOT export d da20 bin shannon 19 2250 gif erase product plf 500 PLOT export d da20 bin shannon 19 2500 gif erase product plf 700 PLOT export d da20 bin shannon 19 2700 gif erase product plf 850 PLOT export d da20 bin shannon 19 2850 gif Using tabular weather data Digital Atmosphere is capable of importing observations from a comma delimited database listing This is excellent for weather observations exported out of a database or a spreadsheet If recognized as shown below Digital Atmosphere the data will be imported and available for viewing as long as it is impo
144. sis to high seas Primary swell Direction from which primary swell waves are originating Secondary swell Direction from which secondary swell waves are originating Page 41 Digital Atmosphere 9 10 9 10 1 Page 42 3 D fields 3 D mode Causes Digital Atmosphere to generate a three dimensional analysis that correlates to the workchart being displayed Upper air radiosonde data is needed for this module to work correctly The analysis is a gridpoint model with a resolution of 31 x 31 x 31 29791 data points How is it constructed A 3 D grid is defined which corresponds to the current workchart All upper air data is looked at including significant level data TTBB and AIREPs and assigned to the closest horizontal gridpoint At each horizontal gridpoint vertical gridpoints are individually checked to see if they fall between two valid upper air data points If so the data is interpolated and fitted to the gridpoint Once this is completed at all horizontal gridpoints they are smoothed horizontally at all levels to blend the data together The result is a 3 D analysis Once prepared there are four ways that a 3 D analysis can be used Isentropic analysis The Isentropic 3 D option is chosen under Level on the speed toolbar When an analysis is chosen you will be asked for an isentropic surface level in deg K Digital Atmosphere will examine the 3 D grid determine the lowest level that the isentropic surface exists
145. sphere directory The View Raw Data panel also has a Find function that lets you search for stations and keywords in the file View raw data A E A 587 sAUS70 KWBC 111200 METAR ESAW 1111462 AUTO 20007KT 105M CLR 19 17 42979 RMK A02 076 S5AU570 KWBC 111200 METAR KFOZ 1111452 AUTO OOOOOKT 105M CLR 09 09 42972 RMK A02 544 540570 KWBC 111200 METAR EMYR 1111452 01007KT 75M SCT200 19 17 A3009 KAPF 1111462 OS005KT 105M FEWLOO 23 22 42996 CB DSNT S5 S1 Y i Find A Repeat find Print Print This option will print your currently active map It s that easy If you want to make changes in the way that the map is printed you ll need to use Print Setup listed below Print sends an exact copy of the screen image to the printer so if the printouts are too dark you will need to change your map settings in Preferences and Digital Atmosphere 6 11 regenerate new maps preferably with white backgrounds then print those Also keep in mind that many PostScript printer drivers will allow you to set the printer to produce negative printouts If the maps are too dark you should avoid using solid colors Regenerate your maps without topography or ocean fills Topography is designed mainly for screen viewing If you absolutely must have dark maps on screen and can t force your printer to produce acceptable output either through File Print Setup or through the printer s own setup menus you will need to export
146. ss and ingest the desired datasets enabling you to plot maps of any date and time between 1961 and 1990 and earlier and later in some cases t import from Archives CD ROM OF ES This option is provided for users of Surface and Upper Archives who wish to have Digital Atmosphere extract and import the datasets A Surface and Upper Archives are a set of y GMT time yy mm dd hh 72 09 04 17 CD ROM drive letter p X Cancel Help Page 13 Digital Atmosphere 6 8 Page 14 In the above example we ve specified that we want data for September 4 1972 at 1700 UTC Greenwich Mean Time It is assumed that the Surface Archives 1961 73 disc is in the drive if the wrong disc is in the drive you will get an error Once the Import item is selected the data will be imported You can then use commands such as Data gt Plots and Analysis gt Sea Level Pressure to view the data Quality control If you re a newcomer to meteorology you ll quickly discover that not all weather data is 100 accurate Errors can get into raw weather data either through transmission problems communications interference human error or simply the observer hitting the wrong key when typing up the report These can either be unnoticable or may corrupt an analysis Fortunately Digital Atmosphere provides a tool to help fix the problem To perform quality control simply drag the mouse over the location where erroneous data
147. t Vandebrande Eliminated problems with Digital Atmosphere resolving FD data times Corrected code to properly evaluate FD forecast hours Thanks to John Souza Quality control has been fixed Some stations would not get QC d and this was due to a problem in the mouse coordinate variables and has been fixed Thanks to Michael Welch and Trevor Cousens Relative humidity in station plots produced an invalid floating point operation this was fixed Thanks to Michael Welch Television plot city font size was not set correctly this has been fixed but not verified Thanks to Jesse Ferrell The location to set Television font colors was not obvious A note has been placed in Preferences under Fonts and in the User Manual to indicate where this is done Thanks to Robert Dale Television plots are now centered horizontally Also a bug where observation times were being ignored in television plots leading to blank maps has been fixed Thanks to Robert Dale Removed Status window on top menu item which is obsolete Thanks to Robert Dale An error was found in the synoptic cloud code import this was fixed Thanks to Michael Welch Stations without sky condition report plotted without a center symbol a plus is now plotted at the observation location The newest 8 05 99 or later version of DIGATMOS SYT is required Topography now works Thanks to Hendricus Lulofs and Trevor Cousens At the end of a File RecompileT
148. t can be generated The workchart will then be redrawn with the specified location You can use this instead of the Map gt Generate map options for creating charts The size of the workchart is dictated by the settings in File gt Preferences gt Maps gt Default Size Note that the entries and their lats longs zooms are loaded from the DIGATMOS MSE file in your Digital Atmosphere directory which you can edit with any text editor Time toolbar Surface time This controls how the valid time for surface data is chosen You should leave it on auto to allow Digital Atmosphere to choose the most popular time from the available data If you wish to override it you can choose manual to be prompted for a time each time you generate a surface product or you can choose a specific numerical time Page 9 Digital Atmosphere 5 5 5 6 Page 10 Upper time This controls how the valid time for upper air data is chosen You should leave it on auto to allow Digital Atmosphere to choose the most popular time from the available data If you wish to override it you can choose manual to be prompted for a time each time you generate an upper air product or you can choose a specific numerical time Valid time Controls whether forecast data is used You should always leave it at analysis unless you are plotting FD winds aloft data Model output data valid times are chosen separately Level This controls the current level Set it to
149. tation data in METAR reports wasn t recognized Readme file updated with new information Error message during Emwin Scheduler when no warning files are found has been eliminated Map tiles have been consolidated from 365 down to 25 files saving 10 MB of disk space when installed fewer wasted blocks in the file allocation tables Some users may see a slight slowdown when generating new maps The new tiles are binary and cannot be edited Users who need to add map information should use the more convenient Custom Overlay files see the Data chapter under Overlay Custom Overlay VERSION 2 3 FINAL BUILD 918 8 20 99 Added two binary files required for program operation DIGATMOS GCI and OUTPUT WRQ Adjusted effects of smart visibility plot to only take effect when left center slot contains visibility data weather symbols or a blank entry This way other data dewpoints etc residing in this slot does not get blanked out when no weather is present The user may still have to adjust the contents of the far left slot for optimum appearance File gt Quality Control now allows editing of pressure tendency pressure trend precipitation amount and period cloud codes and mb and ft levels Inability of File gt Preferences gt Contours settings to save has been rectified settings will always be saved Digital Atmosphere whenever Ok is clicked Fixed a problem with inability to do station plots of FD data and in
150. tation whenever the dewpoint depression is 5 deg C or less If unchecked all station plots are left unfilled Plot model configuration Digital Atmosphere 15 5 4 15 6 15 6 1 A grid of combo boxes are set up in a way that represents the various data positions around a given station plot You can use these combo boxes to adjust the kinds of data that are plotted in the different positions A Save Plot Model and a Load Plot Model option are not provided for upper air plot models since most users will stick to a single configuration Load Loads a predefined upper air plot model configuration Save Saves the upper air plot model configuration for later use Station filtering FT Plot all stations Station plot density im gt Dense 60 Light The station filtering panel is a handy tool for increasing or decreasing the clutter plot density of station plots on the map Users may want to increase the setting to show more useful weather data or decrease it to make a more presentable map Plot all stations When checked Digital Atmosphere will plot every single station that reported a valid meteorological report within the desired timeframe when you choose Overlay Data or Overlay Custom Data This may result in a very cluttered map but can give you an idea of the extent of the data When unchecked Digital Atmosphere will consult the Station Plot Density slider bar to determine how many stations to plot and
151. ter difference between ph1 and ph2 will result in a more curved function while a smaller difference will produce a flatter function For basic users the sine responses are as follows sin 0 0 sin 90 90 sin 180 0 sin 270 1 Amplitude sin ph2 ph1 Value ph1 Finally the amplitude is modified according to the user defined scale and offset values to determine ColorValue which must always be in the range 0 1 0 is dark 1 is bright This means if an Amplitude value is negative it must be offset so that it falls into the range 0 1 An out of bounds ColorValue is always rounded up or down so that it equals 0 or 1 ColorValue Amplitude Scale Offset Example For a basic scale where cold temperatures are black and hot temperatures are bright red set Red s Ph1 0 Ph2 90 Scale 1 and Offset 0 Set the Green and Blue Scale to 0 and Offset to 0 which will always provide a value of O for these components Phi Ph2 Mn Scale multiple Offset absolute D 90 180 MIN MAX Illustration of basic concepts of Ph1 Ph2 Scale and Offset Page 76 Digital Atmosphere Page 77 Digital Atmosphere 16 Troubleshooting 16 1 How to solve a problem If you are having trouble with Digital Atmosphere the best thing to do is consult our online FAQ located on our web site at www weathergraphics com under FAQ This troubleshooting list is kept up to date and has numerous issues that tend to come up If t
152. tor so that they fit within the county Users can edit the locations of these county labels as well as their text content by editing the plaintext file DIGATMOS CXT with any text editor such as Windows Notepad Add highways Overlays United States interstate highways onto the map Add secondary highways Overlays United States U S and state highways onto your map This is a detailed process and may take a few minutes depending upon your computer Add custom overlays Overlays a custom overlay onto the map This is done in the WeatherGraphix style with custom geography residing in the file DIGATMOS PLR Edit this file manually using an ASCII text editor such as Windows Notepad to make changes Note that longitude in the west hemisphere is negative so files imported from WeatherGraphix will need to have the longitude signs inverted The color of the line is controlled by the roads and custom lines setting in File gt Preferences gt Map Add date stamp Adds a date time stamp at the top of the map Digital Atmosphere 8 2 Data Commands Data plots Overlays data plots on the workchart The level at which the data applies is dictated by the Level setting on the Speed Button Toolbar Custom data plots Plots data on the workchart from a custom data file This is intended for use by advanced users A custom data file comprises a package of data that can be readily imported into Digital Atmosphere You can creat
153. uced They allow you to specify the latest synoptic or intermediate synoptic time You can also specify the previous hour as a base token You can easily override the time settings used in Internet time tokens to gain access to data files for different hours The variables that will be used are now shown in the Internet Data Retrieval window Contour color and attribute settings are now in Preferences Contour for easy access Advanced users only if you delete DIGATMOS CGZ Digital Atmosphere will automatically make a new one when you open the Preferences window by importing your older DIGATMOS CCL settings file This is how you can preserve your color schemes when you upgrade You can pick a range of hours to analyze or plot rather than just a specific one when manually selecting an observation time This is great for data sparse areas View EMWIN bulletins using a nested tree structure similar to File Explorer rather than the older series of dropdown menus These bulletins also show the plain English description of each region as well as a more complete description of each product so you can easily see what product you ll be getting Extensive changes have been made in the station tables DIGATMOS STN Three letter ISO 3166 country code identifiers are now being used and the time zone entries have been reformatted and filled to support upcoming capabilities Absolutely no attempt should be made to import station tables using the
154. ude of the defined location Show sounding If you have imported valid rawinsonde upper air data Digital Atmosphere will find the closest rawinsonde station to the defined location and display the SKEW T sounding for that station Show distance Shows the distance between two points previously chosen To set each point right click on the map and choose Set point This must be done twice to define the start and end Then right click anywhere and pick Show distance The lat long of the start and end points along with the distance in nm sm and km will be shown Frontal depiction tools Please refer to the chapter Data gt Frontal Depiction for further information on using these selections Page 11 Digital Atmosphere 6 2 6 4 6 5 Page 12 File Menu Commands Introduction These menu commands are reserved for functions that operate on data files or are significant to Digital Atmosphere s operation Import EMWIN directory This should only be used by users who are running EMWIN This imports all data from the EMWIN directory on the computer It uses the settings in Preferences General to figure which files to use The EMWIN warnings are also imported at this time Import Weatherdish directory This imports all data from the Weatherdish directory on the computer It uses the settings in Preferences General to figure which files to use The Weatherdish warnings are also imported at this time Import file
155. ugh both of those points If you graph the temperatures along this line and gather data from cities along the line your temperature graph will show unique undulations rises and falls These are mathematical waves in the temperature field Assume that you find that the temperature 200 miles on each side of Death Valley along the line is 94 deg F You could then assume most of the southwest United States is hot The temperature graph would show a gradual rise towards Death Valley and a gradual fall as you move away But what if the temperature 200 miles on each side is instead 52 deg F With Death Valley being at 96 this would appear on your graph as a short upward spike at the location corresponding to Death Valley These are two unique mathematical waves the first one with gradual rises and falls means that the temperature field is composed of large or long wavelength features The latter situation with sharp spikes and dips means that the temperature field is composed of short or small wavelength features As you can see gradual changes mean that the meteorological field has long wavelength characteristics and sharp localized changes imply small wavelength features Digital Atmosphere uses a 30 x 30 mesh grid to sample these conditions The mesh is like lines that are drawn across the map 30 across and 30 down to sample the wave structure that is present in the type of analysis you pick Using equally spaced grid points is the easiest
156. um III it takes about 15 seconds That s all there is to it Now you can plot the data analyze it or perform other operations Make sure we re at the surface We want to make sure we re looking at data at the surface so check the time toolbar and make sure Level shows Surface The time toolbar is on the bar below all the shortcut buttons Looking at the big picture Meteorologists usually like to get their first look at a weather chart using isobars lines of equal pressure To display these choose Analysis gt Pressure Height gt Sea level pressure Congratulations You ve made your first weather map You ll notice a deep low over the northern Plains with a Pacific high dominating the western U S and an old polar air mass over the southeastern United States Checking out those fronts It s easy to overlay fronts assuming we saved a certain kind of bulletin produced by the National Weather Service Thankfully this bulletin is packaged right into the tutorial file To see the fronts select Data gt Frontal depiction Even better We can see an old stationary front in the Gulf of Mexico and that the cold front associated with the northern U S low is still north of the border Erasing the map The map is looking a little cluttered huh No problem Just click on Map gt Erase map Ouila All the overlays and markings are gone Looking at station plots Station plots are little packets of data that appear on the map at various locat
157. undaries Format of the ASUS1 KWBC bulletin Finally here is an example of an ASUS1 KWBC bulletin If your Digital Atmosphere 8 7 frontal depiction does not deliver the correct results you can go in and hand edit this bulletin in QUEUE FRT using any text editor 515 ASUS1 KWBC 111919 CODSUS VALID 111118Z HIGHS 1030 41165 1030 38154 1027 45135 1025 31138 1035 6143 1022 3730 1033 5589 1030 6286 LOWS 979 46169 1017 38139 997 4257 997 3865 980 63172 987 66144 998 75113 1005 36102 1013 35112 998 7168 OCFNT WK 46169 46170 45171 COLD WK 45171 44170 42169 40169 40169 39168 WARM WK 45171 46172 47174 46178 COLD WK 38139 36140 33144 31149 31153 STNRY WK 4418 4525 4531 4741 4748 4653 4457 4160 TROF 4257 4151 3647 3145 2845 COLD WK 3865 3763 3463 3164 2869 2673 2478 2384 COLD WK 66144 64142 62142 59142 53145 48149 45153 42156 40162 STNRY WK 55116 59117 62121 65129 67138 69144 69155 68167 68176 STNRY WK 6291 6395 64101 64110 63117 OCFNT WK 76114 77111 78104 7895 7786 7680 COLD WK 36102 34103 32104 31106 TROF 36101 35101 32100 30101 28102 26102 COLD WK 7680 7574 7168 6866 6565 6365 5969 5672 STNRY WK 37103 38104 40106 40109 41111 43114 44117 WARM WK 38101 3999 3897 3795 3791 TROF 48112 51112 55112 TROF 5294 5095 4896 4498 4199 TROF 5571 5270 4968 4767 NNNN Convective Outlooks This option plots convective outlooks thunderstorm forecasts issued by the National Weather Service s Storm Prediction Center SPC in No
158. ving the EMWIN datastream advanced users can use these settings for automatically importing files gathered by their own applications Simply make sure the files are automatically imported into the above directories and filenames TECH TIP Dialup Internet Connections The Internet Scheduler is designed mainly for those who have dedicated Internet connections office networks cable modems and network servers If you use a dialup connection and you use the Internet Scheduler it is possible that your provider may kick you offline at some point especially if there is a period of inactivity You can usually fix this by leaving your E mail program running and have it automatically check E mail every few minutes If you are booted offline Digital Atmosphere cannot renegotiate the connection However when it tries to get more data it will send a signal to your Dialup Networking Remote Access Services in NT asking to reach the network What happens from there is determined by the settings in Dialup Networking or Remote Access Services Once the connection is re established data transfer will resume Windows NT will usually renegotiate lost connections automatically However if you don t have this capability or it s not enough consider shareware programs such as Connect Pal from http www connect pal com Please note that if you are connected continuously to an Internet dialup server your provider may find that you are spending too much time onl
159. way to perform computerized analysis calculations Digital Atmosphere must find where reporting stations are within the grid and try to map the values to that grid taking into consideration how far the reporting station is from a gridpoint and figuring out what to do with gridpoints that aren t assigned any data This is what takes up the majority of processing time So why not just map values to the grids and interpolate between all the points Digital Atmosphere s nearest neighbor technique does something like this It maps data to gridpoints and fills in unassigned gridpoints using Digital Atmosphere 9 3 9 4 9 4 1 9 4 2 the nearest data value a process known as expansion However if the temperature in San Francisco is 52 and in Los Angeles is 85 and assuming we have NO other data the analyzed field anywhere in California will show either 52 or 85 degrees This is clearly not correct so after expansion Digital Atmosphere runs a smoothing algorithm Smoothers smooth out the mesh by changing the value at each gridpoint to an average of itself and its neighbors Unfortunately this can dampen out features in the field Too much smoothing will remove all of the short wavelength features A better way to do this is to use the Weighted Barnes or Cressman techniques These techniques look at each gridpoint find where it corresponds to on the earth and from that location it looks at the values of the stations around it and fi
160. with its scheduler going Adjust for daylight time Check this box if your time zone is currently observing daylight saving time This has an effect on what filenames are downloaded through the Internet when retrieving raw data Default data time selection Default data time selection e Automatic C Manual Determines which data time selection mode will be enabled on the Time Toolbar each time Digital Atmosphere starts up Normally you will want this at Automatic Directories Directories EMIN data directory c weatherwxdatarxfiles EKMAN warning directory fc tweathertwxdatarxfiles Archives and imagewrites i da20wbintarchive Digital Atmosphere always expects its data to be found in the subdirectory called digitalatmospheredirectory data To keep Digital Atmosphere running smoothly never place any binary or unrelated files in this directory With that in mind there are a couple of exceptions where Digital Atmosphere will interact with other directories EMWIN data directory This is the directory where all standard EMWIN bulletins on your system are stored Ignore it if you don t have EMWIN reception Its default setting is the Weathernode default of c weather wxdata rxfiles and should not be changed unless EMWIN data is stored elsewhere on your system EMWIN warning Directory This is the directory where all EMWIN warnings on your system are stored Ignore it if you don t have EMWIN reception
161. y have trouble reading data in coastal locations because of the thicker lines This setting will not take effect until the next time you generate a map Plot ocean fill crosshairs If checked a small cross is plotted at each location where Digital Atmosphere tries to fill the ocean or space with a solid color This is strictly a diagnostic tool which you can use if you want to add or delete points in the ocean fill file Digital Atmosphere GEO FILL GEO It must be used in conjunction with an enabled ocean fill color This setting will not take effect until the next time you generate a map Topography use avg elev rather than max This controls what source of data is used when you select Map gt Make Topography When it is checked average elevation data is used When it is unchecked the maximum elevation data is used Fill outer space When the map is zoomed out to where you can see the disc of the Earth the area outside the disc the outer space area will be filled with the general plot color if this option is selected Label latitude longitude lines When checked and the Lat Long grids are checked and active latitude longitude labels will be placed at the left and bottom of the map consistent with the Grid Interval setting The font color will be the same as the lat long grids and the attributes will be those specified in the Fonts preferences under station plots Digital Atmosphere 15 4 2 15 4 3 JPEG Image Compression
162. you will see an option called Generate Map Simply click on this dropdown menu and pick Illinois The workchart will be redrawn with Illinois in focus Fine tuning the map There s another way you can generate maps for exact areas you want to see Click on Map gt Generate gt Enter lat long Ad That completes the quick tour of Digital Atmosphere This tour was only intended to give you a feel for how Digital Atmosphere works There s lots more to see that is better covered elsewhere in the help files than in this tutorial As soon as you feel ready jump on the Internet or your favorite online service and download new weather data Then poke around and get comfortable with the software There s almost no way you can break it Have fun Page 7 Digital Atmosphere Page 8 Display Components Introduction Before we continue let s look at eight major components of the Digital Atmosphere screen in the illustration below It s important to be familiar with each of these parts since we will refer to them occasionally through the manual This chapter discusses each component in detail t Digital Atmosphere 0f x File Map Data Analysis Internet EMWIN Climatology View Help Main menu FY aaj 5 3 oi Generate map Speed buttons y Surface time Upper time La Valid time analysis meiga R E Al wind n wind plot Barns Derived field NAnalysis tedlbarl Advection Command FO Enter OS DAL te script Timer off

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