the_paragliding_app

Aviation Weather Center API Integration (METAR Format)

API Endpoint

https://aviationweather.gov/api/data/metar

Request Format

curl -s "https://aviationweather.gov/api/data/metar?bbox={minLat},{minLon},{maxLat},{maxLon}&format=json" \
  -H "Accept: application/json" \
  -H "User-Agent: TheParaglidingApp/1.0"

Parameters

• bbox: Bounding box as minLat,minLon,maxLat,maxLon (comma-separated)
• format: json (default is XML)

Example

# Get METAR stations near Annecy (45.9°N, 6.1°E)
curl -s "https://aviationweather.gov/api/data/metar?bbox=45.5,5.7,46.3,6.5&format=json"

Response Format

Returns JSON array of station objects:

[
  {
    "icaoId": "LFLP",
    "name": "Annecy/Meythet Arpt, AR, FR",
    "lat": 45.93,
    "lon": 6.106,
    "elev": 460,
    "reportTime": "2025-10-03T22:00:00.000Z",
    "wdir": 70,      // Wind direction in degrees (0-360)
    "wspd": 4,       // Wind speed in knots
    "temp": 11,      // Temperature in Celsius
    "dewp": 9,       // Dew point in Celsius
    "visib": "6+",   // Visibility in miles ("6+" means 6+ miles)
    "altim": 1020,   // Altimeter setting in hPa
    "cover": "CAVOK", // Cloud cover summary
    "fltCat": "VFR"  // Flight category
  }
]

Extracting Wind Data

Wind Direction (wdir)

• Type: Integer
• Units: Degrees (0-360, where 0/360 = North, 90 = East, 180 = South, 270 = West)
• Missing: Field absent if calm/variable winds

Wind Speed (wspd)

• Type: Integer
• Units: Knots (kt)
• Missing: Field absent if calm winds

Wind Gust (wgst)

• Type: Integer
• Units: Knots (kt)
• Missing: Field only present when gusts are reported

Example Extraction

final response = await http.get(Uri.parse(url));
final List<dynamic> stations = json.decode(response.body);

for (final station in stations) {
  final windDir = station['wdir'];      // null if calm
  final windSpeed = station['wspd'];    // null if calm
  final windGust = station['wgst'];     // null if no gusts
  final stationName = station['name'];

  if (windDir != null && windSpeed != null) {
    final gustStr = windGust != null ? ' gusting ${windGust}kt' : '';
    print('$stationName: ${windSpeed}kt from ${windDir}°$gustStr');
  }
}

Key Fields Reference

Field	Type	Units	Description
icaoId	String	-	ICAO station identifier
name	String	-	Station name and location
lat	Double	degrees	Latitude
lon	Double	degrees	Longitude
elev	Integer	meters	Elevation
wdir	Integer	degrees	Wind direction (0-360)
wspd	Integer	knots	Wind speed
wgst	Integer	knots	Wind gust (only present if gusts reported)
temp	Integer	°C	Temperature
altim	Integer	hPa	QNH pressure
fltCat	String	-	VFR/MVFR/IFR/LIFR

Notes

• METAR updates typically every 30 minutes (at :20 and :50 past the hour for most stations)
• Use reportTime to check data freshness
• Calm winds: wdir and wspd fields may be absent
• Variable winds: wdir may show average or be absent
• No API key required