GeoJSON Service Help

International SIGMETs

Location: /cgi-bin/json/IsigmetJSON.php

This script will create GeoJSON output using data from the ADDS database. The latest set of International SIGMETs are returned. Here is sample output:

{ "type": "FeatureCollection",
    "features": [
    { "type": "Feature",
      "id": "562732",
      "properties": {
          "data": "ISIGMET",
          "icaoId": "NZKL", 
          "firId": "NZZO", 
          "firName": "NZZO AUCKLAND OCEANIC", 
          "seriesId": "48", 
          "hazard": "TURB", 
          "validTimeFrom": "2019-12-30T16:08:00Z", 
          "validTimeTo": "2019-12-30T19:12:00Z", 
          "qualifier": "SEV", 
          "geom": "AREA", 
          "coords": "-57.667,174.500,-47.333,177.833,-42.667,182.667,-56.833,179.500,
          -67.333,168.833,-64.000,162.833,-57.667,174.500", 
          "base": 20000, 
          "top": 46000, 
          "dir": "SE", 
          "spd": "25", 
          "chng": "NC", 
          "rawSigmet": "WSPS21 NZKL 301606\nNZZO SIGMET 48 VALID 301608/302008 NZKL-\n
              NZZO AUCKLAND OCEANIC FIR SEV TURB FCST WI S5740 E17430 - S4720\n
              E17750 - S4240 W17720 - S5650 E17930 - S6720 E16850 - S6400 E16250 -\n
              S5740 E17430 FL200/460 MOV SE 25KT NC="
      },
      "geometry": {
          "type": "Polygon",
          "coordinates": [
              [[174.50,-57.67],[177.83,-47.33],[182.67,-42.67],[179.50,-56.83],
          [168.83,-67.33],[162.83,-64.00],[174.50,-57.67] ]
          ]
      } 
    },
    { "type": "Feature",
      "id": "562705",
      "properties": {
          "data": "ISIGMET",
          "icaoId": "PHFO", 
...

The properties output from the script are:

  • icaoId - ICAO ID that entered the SIGMET
  • firId - Flight Information Region Identifier
  • firName - Long name for the FIR
  • seriesId - The identifier for the series
  • hazard - TS, TSGR (thunderstorms with hail), TURB, LLWS (low level wind shear), MTW (mountain wave), ICING, TC (tropical cyclone), SS (sand storm), DS (dust storm), VA (volcanic ash), RDOACT CLD (radioactive cloud)
  • validTimeFrom - ISO 8601 formatted date and time when SIGMET is first valid
  • validTimeTo - ISO 8601 formatted date and time when SIGMET ends
  • qualifier - hazard qualifier such as ISOL (isolated), SEV (severe), EMBD (embedded), etc
  • geom - Geometry of region (UNK if unable to decode from SIGMET).
  • coords - Coordinates for the geometry. This might be enough information to establish a region such as "N OF N3200".
  • base - Lowest level SIGMET is valid in feet
  • top - Lowest level SIGMET is valid in feet
  • dir - Direction of movement of hazard in degrees
  • spd - Speed of movement of hazard in knots
  • chng - Change of intensity: NC (no change), WKN (weakening), INTSF (intensifying)
  • rawSigmet - Raw SIGMET text

Note: Longitude values will be greater than 180 deg when an International SIGMET crosses the International Date Line. Subtract 360 deg from this value to get the true longitude value.

If the decoder cannot determine a region, the "geom" parameter will specify "UNK" and the geometry output will be an outline for the FIR.

The script can be passed parameters via command line or through CGI REQUEST. The parameters to the script include:

  • type=type - Specifies type of SIGMET to parse: conv, ts, turb, ice, ifr, va, all. The default is all.
  • top=### - Specifies top altitude in 100s feet for returned SIGMETs. The default is no top.
  • bottom=### - Specifies bottom altitude in 100s feet for returned SIGMETs. The default is no top.
  • level=### - Specifies a specific altitude in 100s feet for returned SIGMETs. The default is no level.
  • date=yyyymmddhhnn - This sets the date for the SIGMETs reports. This combined with the age returns all reports within that time range. The default is current time.
  • jsonp=callback - This sets the callback function to be used in a JSONP call. This is just when the script is called on another server. The default is null which outputs straight JSON.