G-AIRMET
G-AIRMET is weather advisory issued by the U.S. National Weather Service. It warns pilots of widespread weather conditions that may affect flights, especially for general aviation and smaller aircraft.
G-AIRMETs are issued for three primary hazard categories:
Turbulence:
Moderate turbulence, Strong surface winds, Low-level wind shear
Icing:
Moderate icing, Freezing level
Ceilings and Visibility:
Widespread low ceilings, Reduced visibility (e.g., fog, precipitation)
API Usage
Our API provides two G-AIRMET endpoints that allow you to determine whether a given ICAO airport identifier or latitude/longitude coordinate falls within one or more active G-AIRMET polygons.
Raw, Short, or Decoded Responses
We offer two API response models for G-AIRMETs - Short and Decoded - allowing you to choose between a summary JSON data or full JSON data including GeoJSON polygon coordinate points for application use.
1. Short Response
Add /short to the end of the endpoint path to receive a simplified JSON response.
Example:
https://api.checkwx.com/v2/gairmet/ktpa/shortResponse:
{
"results": 1,
"data": [
{
"period": {
"issued": "2026-07-09T20:45:00Z",
"expires": "2026-07-10T03:00:00Z"
},
"product": "SIERRA",
"altitude": {
"minimum": {},
"maximum": {
"feet": -1
}
},
"fzl_altitude": {
"minimum": {
"feet": -1
},
"maximum": {
"feet": -1
}
},
"hazard": {
"type": {
"code": "MT_OBSC",
"text": "Mountain obscuration"
}
},
"reason": {
"code": "MTNS OBSC BY CLDS PCPN BR",
"text": "Mountains Obscured by Clouds Precipitation Mist"
}
}
]
}2. Decoded Response
Add /decoded to the endpoint path to receive a full structured JSON format including GeoJSON polygon points.
Example:
https://api.checkwx.com/v2/gairmet/ktpa/decodedResponse:
{
"results": 1,
"data": [
{
"period": {
"issued": "2026-07-09T20:45:00Z",
"expires": "2026-07-10T03:00:00Z"
},
"product": "SIERRA",
"altitude": {
"minimum": {},
"maximum": {
"feet": -1
}
},
"fzl_altitude": {
"minimum": {
"feet": -1
},
"maximum": {
"feet": -1
}
},
"hazard": {
"type": {
"code": "MT_OBSC",
"text": "Mountain obscuration"
}
},
"reason": {
"code": "MTNS OBSC BY CLDS PCPN BR",
"text": "Mountains Obscured by Clouds Precipitation Mist"
},
"geometry": {
"type": "Polygon",
"coordinates": [
[
[
-79.5545,
40.6949
],
[
-79.2971,
40.3178
],
[
-80.0856,
39.3795
],
[
-80.159,
38.3745
],
[
-81.4638,
36.2691
],
[
-82.9467,
35.4512
],
[
-83.7232,
35.7827
],
[
-84.0815,
36.3254
],
[
-83.1672,
36.8981
],
[
-81.8379,
38.8431
],
[
-80.3452,
40.6899
],
[
-79.5545,
40.6949
]
]
]
}
}
]
}G-AIRMET Covering ICAO
Returns all G-AIRMET polygons that are currently covering the specified ICAO
Endpoint Path
/v2/gairmet/{icao}
Path Parameters
icao
string
Required
A single ICAO code (multiple ICAO codes are not allowed)
TAF Nearest to Latitude/Longitude
Returns all G-AIRMET polygons that are currently covering the specified Latitude/Longitude
Endpoint Path
/v2/gairmet/lat/{latitude}/lon/{longitude}
Path Parameters
latitude
float
Required
The latitude in decimal degrees
minimum value: -90
maximum value: 90
longitude
float
Required
The longitude in decimal degrees
minimum value: -180
maximum value: 180
G-AIRMET Fields
The following table lists the fields which are returned by G-AIRMET endpoints
-
icao
string
Examples:
ICAO airport code or station indicator
KPIE -
name
string
Station name
John F Kennedy International Airport -
location
string
City, (State/Province), Country
New York, New York, United States -
period
object
-
issued
string
DateTime the G-AIRMET was issued
2025-12-24 16:00:00 -
expires
string
DateTime the G-AIRMET expires
2025-12-25 16:00:00
-