MADIS Surface Variables - Numeric ----------------------------------------------------------------------------------------------------------------------- Code Name Units Max Notes METAR MARITIME MESO SAO COOP Database QC Level* FSL AWIPS ----------------------------------------------------------------------------------------------------------------------- TD dewpoint temperature K 3 1 X X X X X X X TD1H hourly average dewpoint temperature K 2 1 X X RH relative humidity % 3 1 X X X X X X X RH1H hourly average relative humidity % 2 1 X X Q specific humidity kg/kg 3 1 X X X X X X X Q1H hourly average specific humidity kg/kg 2 1 X X DPD dewpoint depression K 3 1 X X X X X X X DPD1H hourly average dewpoint depression K 2 1 X X AH absolute humidity g/(m**3) 3 1 X X X X X X X AH1H hourly average absolute humidity g/(m**3) 2 1 X X ALTSE altimeter Pa 3 2 X X X X X X WVMR water vapor mixing ratio kg/kg 3 1 X X X X X X X PT3 3 hour pressure change Pa 2 3 X X X X X X PT3CHR character of 3h pressure change code 0 3 X X X X X X SLP sea level pressure Pa 3 X X X X X X P station pressure Pa 3 2 X X X X X X T air temperature K 3 4 X X X X X X X T1H hourly average temperature K 2 4 X X TV virtual temperature K 3 4 X X X X X X X TV1H hourly average virtual temperature K 2 4 X X DD wind direction deg 3 5 X X X X X X X DD1H hourly average wind direction deg 1 5 X X DD24H daily average wind direction deg 1 5 X X FF wind speed m/s 3 5 X X X X X X X FF1H hourly average wind speed m/s 2 5 X X FF24H daily average wind speed m/s 1 5 X X U u wind component m/s 3 5 X X X X X X X U1H hourly average u wind component m/s 2 5 X X U24H daily average u wind component m/s 1 5 X X V v wind component m/s 3 5 X X X X X X X V1H hourly average v wind component m/s 2 5 X X V24H daily average v wind component m/s 1 5 X X VIS visibility m 1 X X X X X X VERTVIS vertical visibility m 0 X X WMOID WMO station number 0 X X X X X ELEV elevation m 0 X X X X X X X LAT latitude deg N 0 X X X X X X X LON longitude deg E 0 X X X X X X X PLATTYP data platform type code 0 6 X X X X PLATDIR platform true direction deg 0 X X X PLATSPD platform true speed m/s 0 X X X CORR correction flag code 0 X X X X PCPTOTL total precipitation m 0 30 X X X X PCP1H accumulated precip - 1h m 1 7 X X X X X X X PCP3H accumulated precip - 3h m 1 X X X X PCP6H accumulated precip - 6h m 1 X X X X X PCP12H accumulated precip - 12h m 1 X X X PCP18H accumulated precip - 18h m 1 X X X PCP24H accumulated precip - 24h m 1 X X X X X X X PCPLM accum. precip - since local midnight m 1 X X X PCPUTCM accum. precip - since UTC midnight m 1 X X X PCPCDAY accum. precip - local calendar day m 1 X X PCPUDAY accum. precip - user-defined day m 1 22 X X UDSTART user-defined day start HHMM 22 X X PCPRATE precipitation rate kg/(m**2)/s 1 7 X X X X X X X PCPINT precipitation intensity code 0 8 X X X PCPTYPE precipitation type code 0 9 X X X SKYCVLB sky cover layer base m 0 10 X X X X LCLHT height of the lowest cloud layer code 0 11 X X X LLCTYPE low level cloud type code 0 12 X X X MLCTYPE middle level cloud type code 0 13 X X X HLCTYPE high level cloud type code 0 14 X X X CLDFRAC fraction of sky covered by clouds tenths 0 X X X T24MIN 24 hour minimum temperature K 1 X X X X X T24MAX 24 hour maximum temperature K 1 X X X X X FUELM Fuel moisture % 0 X X FUELT Fuel temperature K 0 X X SOILM Soil moisture tension kPa 0 X X SOILMP Soil moisture percent % 1 X X SOILM2 soil moisture percent - 2 inch % 1 X X SOILM4 soil moisture percent - 4 inch % 1 X X SOILM8 soil moisture percent - 8 inch % 1 X X SOILM20 soil moisture percent - 20 inch % 1 X X SOILM40 soil moisture percent - 40 inch % 1 X X SOILT Soil temperature K 2 X X SOILT2 soil temperature - 2 inch K 2 X X SOILT4 soil temperature - 4 inch K 2 X X SOILT8 soil temperature - 8 inch K 2 X X SOILT20 soil temperature - 20 inch K 2 X X SOILT40 soil temperature - 40 inch K 2 X X DDGUST wind dir at gust deg 1 X X X FFGUST wind gust m/s 2 X X X X X X DDMAX maximum wind direction deg 0 X X DDMAX1H wind dir at hourly max wind speed deg 1 X X FFMAX maximum wind speed m/s 0 X X FFMAX1H hourly maximum wind speed m/s 2 X X PSWDIR direction of primary swell waves deg 0 X X X PSWHT primary swell wave height m 0 X X X PSWPER primary swell wave period s 0 X X X SSWDIR direction of secondary swell waves deg 0 X X X SSWHT secondary swell wave height m 0 X X X SSWPER secondary swell wave period s 0 X X X SST sea surface temperature K 2 X X X X TIDEDEP tide departure from predicted level m 0 X X TIDEIND tide indicator code 0 15 X X WAVEHT wave height m 0 X X X WAVEPER wave period s 0 X X X WAVESTP wave steepness 0 X X WWVEPER wind wave period s 0 X X WWVEHT wind wave height m 0 X X HRWVEHT high resolution wave height m 0 X X X EQFF10M equivalent wind speed at 10 m m/s 0 X X X EQFF20M equivalent wind speed at 20 m m/s 0 X X X SNOWC snow cover m 1 X X X SNOW6H snow fall - 6h m 1 X X SNOW24H snow fall - 24h m 1 X X FSRDINS diffuse solar radiation - instant. watt/(m**2) 0 X X X FSRD5M diffuse solar radiation - 5min watt/(m**2) 0 X X X FSRD15M diffuse solar radiation - 15min watt/(m**2) 0 X X X FSRD1H diffuse solar radiation - 1h watt/(m**2) 0 X X X FSRD24H diffuse solar radiation - 24h watt/(m**2) 0 X X X DSRDINS direct solar radiation - instant. watt/(m**2) 0 X X X DSRD5M direct solar radiation - 5min watt/(m**2) 0 X X X DSRD15M direct solar radiation - 15min watt/(m**2) 0 X X X DSRD1H direct solar radiation - 1h watt/(m**2) 0 X X X DSRD24H direct solar radiation - 24h watt/(m**2) 0 X X X GSRDINS global solar radiation - instant. watt/(m**2) 0 X X X GSRD5M global solar radiation - 5min watt/(m**2) 0 X X X X GSRD15M global solar radiation - 15min watt/(m**2) 0 X X X GSRD1H global solar radiation - 1h watt/(m**2) 0 X X X GSRD24H global solar radiation - 24h watt/(m**2) 0 X X X SOLRAD solar radiation - unknown type watt/(m**2) 0 X X X TD10C dewpoint from tenths of a deg C K 0 16 X X X T10C temperature from tenths of a deg C K 0 16 X X X TWB wet bulb temperature K 0 X X X PWV GPSMET precipitable water vapor m 0 X X GPSTSD GPSMET total signal delay m 0 X X GPSDSD GPSMET dry signal delay m 0 X X GPSWSD GPSMET wet signal delay m 0 X X GPSMWT GPSMET mean weighted temperature K 0 X X GPSFE GPSMET formal error m 0 X X GPSWDMF GPSMET wet delay mapping function 0 X X RDT1 Road temperature - sensor 1 K 0 X X RDT2 Road temperature - sensor 2 K 0 X X RDT3 Road temperature - sensor 3 K 0 X X RDT4 Road temperature - sensor 4 K 0 X X RDLFT1 Road liquid freeze temp - sensor 1 K 0 X X RDLFT2 Road liquid freeze temp - sensor 2 K 0 X X RDLFT3 Road liquid freeze temp - sensor 3 K 0 X X RDLFT4 Road liquid freeze temp - sensor 4 K 0 X X RDLCF1 Road liquid chem factor - sensor 1 0 X X RDLCF2 Road liquid chem factor - sensor 2 0 X X RDLCF3 Road liquid chem factor - sensor 3 0 X X RDLCF4 Road liquid chem factor - sensor 4 0 X X RDLCP1 Road liquid chem percent - sensor 1 % 0 X X RDLCP2 Road liquid chem percent - sensor 2 % 0 X X RDLCP3 Road liquid chem percent - sensor 3 % 0 X X RDLCP4 Road liquid chem percent - sensor 4 % 0 X X RDLIP1 Road liquid ice percent - sensor 1 % 0 X X RDLIP2 Road liquid ice percent - sensor 2 % 0 X X RDLIP3 Road liquid ice percent - sensor 3 % 0 X X RDLIP4 Road liquid ice percent - sensor 4 % 0 X X RDLDP1 Road liquid depth - sensor 1 m 0 X X RDLDP2 Road liquid depth - sensor 2 m 0 X X RDLDP3 Road liquid depth - sensor 3 m 0 X X RDLDP4 Road liquid depth - sensor 4 m 0 X X RDSTA1 Road state - sensor 1 code 0 17 X X RDSTA2 Road state - sensor 2 code 0 17 X X RDSTA3 Road state - sensor 3 code 0 17 X X RDSTA4 Road state - sensor 4 code 0 17 X X RDSUBT1 Road subsurface temp - sensor 1 K 0 X X RDSUBT2 Road subsurface temp - sensor 2 K 0 X X RDSUBT3 Road subsurface temp - sensor 3 K 0 X X RDSUBT4 Road subsurface temp - sensor 4 K 0 X X BATVLT battery voltage volt 0 X X BATVLT2 secondary battery voltage volt 0 X X RIVSTG river stage m 0 X X STNSPC1 station specific #1 0 25 X X STNSPC2 station specific #2 0 25 X X COMSTAT commissioned status code 0 26 X X STAQUAL station quality indicator code 0 27 X X DOORIND door open/closed indicator code 0 31 X X HEATIND rim heating on/off indicator code 0 32 X X BUCKLEV precipitation bucket level % 0 X X RIMT precipitation rim temperature K 0 X VIBWD1 vibrating wire depth - 1 mm 0 X VIBWD2 vibrating wire depth - 2 mm 0 X VIBWD3 vibrating wire depth - 3 mm 0 X MLLW mean lower low water m 0 X X MADIS Surface Variables - Character ----------------------------------------------------------------------------------------------------------------------- Code Name Character Notes METAR MARITIME MESO SAO COOP Database Size FSL AWIPS ----------------------------------------------------------------------------------------------------------------------- AUTOTYP automated station type 6 18 X X X X REPTYPE report type 6 19 X X X X PRESWEA present weather 25 20 X X X X X SKYCOV sky cover 6x8 10 X X X X STALOC station location 51 21 X X X X X SUBPVDR subprovider 11 29 X X X X T24MINT time of 24 hour minimum temperature 9 28 X T24MAXT time of 24 hour maximum temperature 9 28 X Notes ----- 1. Dewpoint temperature and/or relative humidity are the moisture variables stored in the database. The user can select either of these variables, or select dewpoint depression, specific humidity, absolute humidity, or water vapor mixing ratio which will then be calculated by the MADIS API. If available, the stage 3 QC results from the dewpoint variable will be used for any of the calculated variables. If this isn't available, the QC results from the stored RH variable will be used. Also note that pressure is needed for the absolute humidity conversion; for the COOP dataset this is done by using the U.S. Standard Atmosphere calculation to calculate pressure from station elevation. 2. As altimeter and station pressure can be calculated from each other, for datasets without altimeter (MARITIME) the altimeter will be calculated by the MADIS API, and for datasets without station pressure (METAR, SAO) that variable will be calculated as well. With the MESO dataset, if the stored variable isn't the one requested by the user for each particular station, the calculated value will be returned. In all cases, the stage 3 QC from the altimeter variable (if available) will be applied. 3. The 3 hour pressure change value consists of the numeric pressure change value, with a sign applied per the value in the character of 3h pressure change variable. The latter variable is coded: Value Meaning ----- ------- 0 pressure same or higher than 3 hours ago 1 increasing then steady 2 increasing 3 decreasing or steady, then increasing 4 steady 5 pressure same or lower than 3 hours ago 6 decreasing 7 steady or increasing, then decreasing 4. Air temperature is the temperature variable stored in the database. The user can optionally select virtual temperature, which will then be calculated by the MADIS API. The QC results from air temperature will apply in either case. Also note that if virtual temperature cannot be calculated (missing or bad dewpoint or pressure), and the air temperature passed all QC checks, the air temperature will be returned instead, and a QC data descriptor value of "T" will be assigned. As with the absolute humidity conversion mentioned above, the virtual temperature conversion done for the COOP dataset uses pressure calculated from the station elevation. 5. Wind speed and direction are reported and stored in the database. The user can optionally select u & v wind components and those will be calculated and returned. The QC results from speed and direction will be used In either case, and if one of the map projections has been selected via the MSETDOM call, the winds will be rotated to match the projection. 6. Data platform type (MARITIME): Value Meaning ----- ------- 0 stationary (moored buoy or CMAN) 1 moving (drifting buoy or ship) Data platform type (COOP): Value Meaning ----- ------- < 100 Phase II site (regional hub) 100 Phase II site (GOES/HADS) 200 Phase I site (direct connect) 300 Phase I site (GOES/HADS) The modernized NWS Cooperative Observer sites can provide different variables, and on different schedules, dependent both on the type of site (Phase I or II) and on the processing done as part of reformatting the data sent over the various communications systems in use. Here are the primary differences: - Phase I sites only report a single temperature observation per hour, valid at minute 0. - Phase II GOES/HADS sites only report once per hour, but the reports contain 5-minute observations from the last hour. 7. The user can select either accumulated precip - 1h or precipitation rate. Whichever variable is actually stored in the MADIS database will be converted to the form desired by the caller. 8. Precipitation intensity (MESONET): Value Meaning ----- ------- 0 intensity info not available 1 none 2 light 3 moderate 4 heavy 5 slight 6 other Stations measuring precipitation type and intensity may take observations with one or two sensors. Therefore, an array of 2 elements will be returned for each record, and the caller should dimension the array to (2,200000). 9. Precipitation type (MESONET): Value Meaning ----- ------- 0 no precipitation 1 precipitation present but unclassified 2 rain 3 snow 4 mixed rain and snow 5 light 6 light freezing 7 freezing rain 8 sleet 9 hail 10 other 11 unidentified 12 unknown 13 frozen 14 ice pellets 15 recent 29 RPU-to-maxSensor communications failure 30 sensor failure Stations measuring precipitation type and intensity may take observations with one or two sensors. Therefore, an array of 2 elements will be returned for each record, and the caller should dimension the array to (2,200000). 10. The sky cover variables (METAR, SAO) have 6 different layers (array elements) for each record. The "sky cover layer base" variable is a number, so it should be dimensioned to (6,200000) by the caller. The character "sky cover" variable gives information about each layer reported in the sky cover layer base variable, and has 8 characters for each of the 6 layers, so it should be dimensioned character*8 skycover(6,200000). For more information on these variables, see section 9.4.2 of Federal Meteorological Handbook 1 (FMH-1). A PDF version of FMH-1 is available at http://www.ofcm.gov/fmh-1/fmh1.htm. Sky cover values: Value Meaning Summation amount of layer ----- ------- ------------------------- VV Vertical Visibility 8/8 SKC or CLR Clear 0 FEW Few 1/8 - 2/8 SCT Scattered 3/8 - 4/8 BKN Broken 5/8 - 7/8 OVC Overcast 8/8 1. CLR is used at automated stations when no layers at or below 12,000 ft are reported; SKC is used at manual stations when no layers are reported. 2. Any layer amount less than 1/8 is reported as FEW. 11. Height of the lowest cloud layer (MARITIME): Value Meaning ----- ------- 0 0 to 100 ft 1 200 to 300 ft 2 400 to 600 ft 3 700 to 900 ft 4 1000 to 1900 ft 5 2000 to 3200 ft 6 3300 to 4900 ft 7 5000 to 6500 ft 8 7000 to 8000 ft 9 8500 or higher or no clouds -1 unknown or cloud base below surface of station 12. Low level cloud type (MARITIME): Value Meaning ----- ------- 0 no Cu, Cb, Sc, or St 1 Cu w/ little vertical extent 2 Cu w/ moderate or great vertical extent 3 Cb w/out fibrous or striated upper part 4 Sc formed by spreading Cu 5 Sc not formed by spreading Cu 6 St or ragged St 7 ragged St or ragged Cu 8 Cu and Sc w/ bases at different levels 9 Cb w/ fibrous or striated upper part -1 low clouds not visible (obscured) 13. Middle level cloud type (MARITIME): Value Meaning ----- ------- 0 no Ac, As, or Ns 1 semi-transparent As 2 opaque As, or Ns 3 semi-transparent Ac predominant 4 Ac continually changing in appearance 5 Ac invading the sky 6 Ac formed by spreading of Cu or Cb 7 double layered Ac or thick Ac; or Ac & As 8 turreted Ac or Ac in tufts 9 Ac of a chaotic sky -1 middle clouds not visible (obscured) 14. High level cloud type (MARITIME): Value Meaning ----- ------- 0 no Ci, Cs, or Cc 1 Ci in filaments or hooks 2 dense Ci & turreted Ci & Ci in tufts 3 dense Ci orig from Cb, present 4 Ci invading the sky 5 Cs not exceeding 45 degrees altitude 6 Cs exceeding 45 degrees altitude 7 Cs covering the whole sky 8 Cs not invading the sky 9 Cc alone, or Cc more than (Ci & Cs) -1 high clouds not visible (obscured) 15. Tide indicator (MARITIME): Value Meaning ----- ------- 0 Data not available 1 Low tide, observed tide below predicted level 2 Low tide, observed tide same as predicted level 3 Low tide, observed tide above predicted level 4 Neither low nor high tide, observed tide below predicted level 5 Neither low nor high tide, observed tide same as predicted level 6 Neither low nor high tide, observed tide above predicted level 7 High tide, observed tide below predicted level 8 High tide, observed tide same as predicted level 9 High tide, observed tide above predicted level 16. The dewpoint & temperature from tenths of a deg C variables (METAR) are decoded from the remarks section of the raw reports, for designated stations only, and have values rounded to the nearest 0.1 degree C. The primary temperature and dewpoint variables are reported from all stations, and in the raw reports, are rounded to the nearest whole degree C. 17. Road state (MESONET): Value Meaning ----- ------- 0 No report 1 Dry 2 Moist 3 Moist and chemically treated 4 Wet 5 Wet and chemically treated 6 Ice 7 Frost 8 Snow 9 Snow/Ice watch 10 Snow/Ice warning 11 Wet above freezing 12 Wet below freezing 13 Absorption 14 Absorption at dewpoint 15 Dew 16 Black ice warning 17 Other 18 Slush 18. Automated station type (METAR, SAO): Value Meaning ----- ------- AO1 automated station without precipitation discriminator (METAR) AO2 automated station with precipitation discriminator (METAR) AUTO2 automated station (SAO) AUTO4 automated station (SAO) AUTO7 automated station (SAO) AUTO8 automated station (SAO) blank manual station 19. Report type (METAR, SAO): Value Meaning ----- ------- METAR scheduled report (METAR) SPECI report triggered by SPECI criteria (METAR) (see FMH-1) SA scheduled report (SAO) 20. The coded values for the present weather variable (METAR, MARITIME) are too extensive to list in this document. See FMH-1, particularly section 12.6.8. A PDF version of FMH-1 is available at http://www.ofcm.gov/fmh-1/fmh1.htm. The coded values for the COOP present weather variable are listed below: Value Meaning ----- ------- - No report FG Fog IE Ice GL Glaze TS Thunder GR Hail DW Damaging Winds RA Rainy SN Snowy 21. The station location (METAR, MESO, COOP) generally contains a geographic description of the station's location, typically including the city, state, and sometimes the country. With the mesonet dataset, in addition, characters (40:50) are used to denote the "subprovider", if any. Some (but not all) mesonets contain data from a number of smaller networks. In these cases, the "subprovider" for each station is the name of the smaller network. If this field is all blank, then there isn't a subprovider associated with the station. This information can also be obtained directly by reading the SUBPVDR variable, which only contains the subprovider designation. Note that the station location variable isn't available in the AWIPS database for METAR. 22. The PCPUDAY (COOP) variable provides the accumulated precipitation for a 24 hour period that can be defined by each individual station. The UDSTART variable can be used to determine the start hour & minute of the "user-defined day". E.g., a UDSTART value of 1330 would mean the 24 hour accumulation period starts at 13:30 local time, a value of 200 would represent 02:00. 23. [reserved] 24. [reserved] 25. The COOP stations have the option to add up to two variables that are specific to the individual station. 26. Commissioned status (COOP): Value Meaning ----- ------- 0 commissioned 1 not yet commissioned 27. Station quality indicator (COOP): Value Meaning ----- ------- [TBD] 28. All times reported in the MADIS API are in Universal Coordinated Time, with the format of "YYJJJHHMM", where: YY = 2-digit year (good from 1980 - 2179) JJJ = Julian date of the year (1-366) HH = Hour (0-23) MM = Minute (0-59) If the max/min temperature time is missing, the 9-character field will be set to all blanks, e.g., " ". Users of the MADIS API sfcdump program will get the time output in their chosen format, either YYJJJHHMM or YYYYMMDD_HHMM. 29. Some (but not all) mesonets, and the COOP dataset, contain data from a number of smaller networks. In these cases, the "subprovider" for each station is the name of the smaller network. If this variable is all blank, then there isn't a subprovider associated with the station. 30. The total precipitation variable (COOP, MESO) is an accumulation over a period of unknown duration. Stations that report this value will also report the PCP1H and PCP24H observations. The PCPTOTL value is made available for those interested in calculating the accumulation over a period of other than 1 or 24 hours. 31. The COOP door open/closed indicator is used to show when the instrument enclosure has been opened for maintenance. Value Meaning ----- ------- 0 closed 1 open 32. The COOP rim heating on/off indicator is used to indicate when rim heating is on for the precipitation gauge. Value Meaning ----- ------- 0 off 1 on * The QC information is only available with the FSL database for all datasets other than MESO, which does have the QC in the AWIPS database.