Graphical Airmen's Meteorological Information (G-AIRMET) Weather Advisories

A G-AIRMET is a graphical advisory of weather that may be hazardous to aircraft, but are less severe than SIGMETs. They are valid at specific time "snapshots". The G-AIRMET forecasts are distributed in XML (USWX) format. The USWX XML files contain forecaster-created graphical objects which depict hazard areas and attributes. G-AIRMETs are issued at discrete times 3 hours apart for a period of up to 12 hours into the future (00, 03, 06, 09, and 12 hours). They are issued at 03:00, 09:00, 15:00 and 21:00 UTC (with updates issued as necessary). G-AIRMETs are issued by the AWC for the lower 48 states and adjacent coastal waters. The G-AIRMET USWX XML files are currently disseminated from AWC to the operational NGITWS system, and from AWC to the NWSTG for dissemination over NOAAPort. AWC provides the legacy AIRMET information via traditional alphanumeric code (TAC), which is currently archived at NCEI. The G-AIRMET data in BUFR format was operational from 2010 to 2022 and was not archived. This data archive includes the USWX XML formatted products starting on January 1, 2023.