National Weather Service API (api.weather.gov)

For your project

Official API

Official API · Free User-Agent required; rate limit not public but 'generous for typical use'; over the limit, retry after it clears (typically within 5 seconds)

“The API is based upon of JSON-LD to promote machine data discovery. The API is located at: https://api.weather.gov” weather.gov/documentation/services-web-api

Key

Not needed

“A User Agent is required to identify your application. This string can be anything, and the more unique to your application the less likely it will be affected by a security event.” weather.gov/documentation/services-web-api

Formats

GEOJSON, JSON-LD, XML, CAP, ATOM

Data download

Not stated

License

public domain (US Government work) Information on NWS web pages and API data, unless noted otherwise; do not claim it as your own, imply NOAA endorsement, or present modified content as official

Commercial use

Commercial use OK

“All of the information presented via the API is intended to be open data, free to use for any purpose.” weather.gov/documentation/services-web-api

Credit

No credit needed

“third parties producing copyrighted works consisting predominantly of the material appearing in NWS Web pages must provide notice with such work(s) identifying the NWS material incorporated and stating that such material is not subject to copyright protection.” weather.gov/disclaimer

Embedding

Embedding with conditions

“so long as you do not: 1) claim it is your own (e.g., by claiming copyright for NWS information -- see below), 2) use it in a manner that implies an endorsement or affiliation with NOAA/NWS, or 3) modify its content and then present it as official government material.” weather.gov/disclaimer

Using the website

Free

Read on National Weather Service API (api.weather.gov)'s own pages on Oct 23, 2026 · license or terms · API docs. Check the license page before you ship.

What you can build

• A severe-weather notifier that polls /alerts/active?area={state} and pushes new tornado, flood or heat warnings to a Discord or SMS channel.
• A US road-trip planner that looks up the 12-hour forecast periods for each overnight stop along a route.
• A farm or event dashboard that caches the hourly grid forecast for fixed sites and shows rain probability and wind for the next 7 days.