Aviation Weather Center Data API

What you can build

• Hold air freight when the hub goes IFR

  The operator reads the METAR and TAF for your carrier's hub airports. When a convective SIGMET or low ceilings cover the window, it proposes a hold on affected shipments with the raw report attached.

  With Weather Hold

• Re-time the airport shuttle on a bad-weather morning

  Before the first run, the operator checks the airport METAR and TAF and proposes a later departure or an extra loop, citing visibility and wind from the report.

  With Shuttle Timing

• Warn field crews of convective weather

  The operator polls SIGMETs and G-AIRMETs over the box around your sites and proposes a notice to crews when a convective or turbulence advisory lands inside it.

  With Severe Weather Notice

Requirements

• ICAO station ids (one, a comma list, or a state as @WA) or a bbox of lat0, lon0, lat1, lon1 for most endpoints
• A poll interval that respects the products: most METARs update once per hour and TCF is issued every other hour
• Handling for status 204, which AWC returns for a valid request with no data, except in GeoJSON
• The cache files under /data/cache for full datasets instead of large or frequent custom queries

Authentication

No key or account. The endpoints answer plain HTTPS GET requests; AWC asks you to set a custom user agent so automated filtering does not block you.

Limits

• All requests are rate limited to 100 requests per minute; exceeding it returns 429 and can get access blocked
• Most endpoints return a maximum of 400 entries, and the database holds only the previous 30 days
• Cross-origin resource sharing is not permitted, and undocumented query parameters return an error
• CONUS text AIRMETs were discontinued in January 2025; G-AIRMETs replace them, and /api/data/airmet covers Alaska only

Questions and answers

Do you need an API key for the AWC Data API?

No. The endpoints under /api/data answer plain HTTPS GET requests. AWC asks you to keep requests limited in scope and frequency, set a custom user agent, and use the cache files for larger datasets.

What formats does the API return?

It depends on the product. METARs come as raw text, decoded, JSON, GeoJSON, XML, or IWXXM; TAFs as raw, JSON, GeoJSON, XML, or IWXXM; domestic SIGMETs as raw, JSON, GeoJSON, or XML. Station, airport, and navaid records come as JSON, GeoJSON, or XML.

How often do the cache files update?

METARs, CONUS SIGMETs, G-AIRMETs, and aircraft reports once a minute; TAFs every 10 minutes; the stations listing once a day. All files are gzipped text under /data/cache.