# Free Weather and Climate Data APIs for Developers

Where to get forecasts, radar, climate history and air quality for your app: open services from weather agencies, with their keys, limits and licenses, and the commercial weather APIs next to them.

## Open sources

- Open-Meteo: A JSON weather API that serves forecasts from 30+ national weather models plus hourly historical weather back to 1940, with sister APIs for air quality, marine, flood, elevation and geocoding. [API, no key; commercial use with conditions] https://agentgid.com/resources/open-meteo/agent.md
- MET Norway Weather API: The free forecast API behind Yr: give it a latitude and longitude anywhere in the world and get a point forecast (temperature, wind, rain, cloud, UV, weather symbol) as JSON or legacy XML. [API, no key; commercial use ok] https://agentgid.com/resources/met-norway-locationforecast/agent.md
- National Weather Service API (api.weather.gov): The official US weather service API: forecasts for any US grid point, hourly forecasts, station observations and active watches and warnings, served as GeoJSON and other formats. [API, no key; commercial use ok] https://agentgid.com/resources/nws-api/agent.md
- NOAA NCEI Climate Data Online and Access Data Service: NOAA's archive of historical weather and climate observations, including daily station records (GHCN-Daily) from over 90,000 land stations, with a key-less data service API, a token-based CDO API and bulk file downloads. [API, no key; commercial use with conditions] https://agentgid.com/resources/noaa-ncei-climate-data-online/agent.md
- ECMWF Open Data: A free subset of ECMWF's real-time global forecasts from its physics model (IFS) and its machine-learning model (AIFS), published as GRIB2 files four times a day on a download portal and mirrored on AWS, Azure and Google Cloud. [API, no key; commercial use ok] https://agentgid.com/resources/ecmwf-open-data/agent.md
- Copernicus Climate Data Store (CDS): The EU's climate data catalogue: reanalyses such as ERA5 (hourly global weather back to 1940), satellite records, seasonal forecasts and climate projections, downloadable through web forms or the cdsapi Python client with a free account. [API with key; commercial use ok] https://agentgid.com/resources/copernicus-climate-data-store/agent.md
- DWD Open Data Server: Germany's national weather service file server: ICON model forecasts (GRIB2), radar composites, live station observations, severe-weather warnings (CAP) and long climate station records from its Climate Data Center, all as plain HTTPS downloads. [no API; commercial use ok] https://agentgid.com/resources/dwd-open-data/agent.md
- NASA POWER (Prediction Of Worldwide Energy Resources): A NASA API and data viewer giving satellite- and model-derived solar radiation and weather for any point on Earth, with 300+ parameters at hourly, daily, monthly and climatology levels, in units tailored for renewable energy, buildings and agriculture. [API, no key; commercial use ok] https://agentgid.com/resources/nasa-power/agent.md
- RainViewer Weather Maps API: A free public JSON index plus PNG map tiles of a global weather-radar composite built from 1200+ radars, covering the past 2 hours with nowcast frames, ready to drop on a Leaflet or MapLibre map. [API, no key; commercial use with conditions] https://agentgid.com/resources/rainviewer-api/agent.md
- OpenAQ: An open platform that collects air-quality measurements (PM2.5, PM10, ozone, NO2 and more) from government monitors and low-cost sensors worldwide and serves them through a free keyed REST API and a key-less daily CSV archive on AWS S3. [API with key; commercial use with conditions] https://agentgid.com/resources/openaq/agent.md
- Windy: An animated world weather map showing wind, rain, temperature, waves and more from several forecast models, plus official APIs for point forecasts, embeddable forecast maps and webcams. [API with key; commercial use with conditions] https://agentgid.com/resources/windy/agent.md
- Zoom Earth: A browser map of the whole planet that layers near-live weather satellite pictures, rain radar, model forecasts, storm tracks and active fires. [no API; non-commercial only] https://agentgid.com/resources/zoom-earth/agent.md
- LightningMaps.org: A real-time map of lightning strikes located by a volunteer network of home-built radio receivers run by the Blitzortung.org community. [no API; commercial use with conditions] https://agentgid.com/resources/lightningmaps-blitzortung/agent.md

## Commercial APIs (prices checked on official pages)

- OpenWeather API: Current weather, forecasts, air pollution, weather maps and geocoding API. https://agentgid.com/apis/openweathermap/agent.md
- Weatherstack API: Provides real-time and historical weather data for global locations via API. https://agentgid.com/apis/weatherstack/agent.md

## Libraries

- Leaflet: Lightweight JavaScript library for creating mobile-friendly interactive maps. https://agentgid.com/tools/leaflet/agent.md
- MapLibre GL: Open-source WebGL interactive maps library with BSD license and community support. https://agentgid.com/tools/maplibre-gl/agent.md
- Chart.js: Simple HTML5 canvas-based charting library for creating interactive data visualizations. https://agentgid.com/tools/chart-js/agent.md
- Luxon: Immutable date and time library with timezone, formatting and parsing support. https://agentgid.com/tools/luxon/agent.md

## Build ideas

- Rain in the next hour: an alert for your city: https://agentgid.com/resources/ideas/rain-alert-for-your-city/agent.md