Last updated August 13, 2026
WeatherMetro is built entirely on open data. Nothing here is resold from a commercial weather vendor - we ingest official model output from national weather services and run our own pipeline. Several of these licences require attribution, and all of them deserve it: this page is that credit, and it is also the definitive answer to "where does this number come from?"
Using our API? On the free plan, display "Weather data by WeatherMetro" with a link back. This page names every upstream source we build on - linking to it is the simplest way to stay compliant with the licences below.
| SOURCE | WHAT WE USE | LICENCE |
|---|---|---|
| ECMWF | IFS and AIFS open data - the global backbone of our forecasts | CC BY 4.0 |
| NOAA / NWS | GFS, HRRR, GEFS ensemble, NBM; severe-weather alerts | Public domain (U.S. Government) |
| Deutscher Wetterdienst | ICON global, ICON-EU, ICON-D2 | CC BY 4.0 |
| Météo-France | AROME, ARPEGE | Licence Ouverte / Etalab 2.0 |
| Environment and Climate Change Canada | GEM global & regional | ECCC open data licence |
| MeteoSwiss | ICON-CH1 / ICON-CH2 ensembles | CC BY 4.0 |
| Other national services | Model output from JMA, KMA, CMA, BOM, DMI, KNMI, ItaliaMeteo, Met Éireann and GeoSphere Austria, redistributed through Open-Meteo | CC BY 4.0 and equivalents |
| SOURCE | WHAT WE USE | LICENCE |
|---|---|---|
| NOAA MRMS | Multi-radar precipitation-rate mosaics, refreshed every two minutes - the basis of our radar map and minute-scale nowcast | Public domain |
| NOAA Aviation Weather Center | METAR station observations (also our forecast-verification truth data) | Public domain |
| pySTEPS | Optical-flow nowcasting library used to extrapolate radar up to two hours ahead | BSD 3-Clause |
| SOURCE | WHAT WE USE | LICENCE |
|---|---|---|
| Copernicus Atmosphere Monitoring Service (CAMS) | Global air quality and UV; European pollen forecasts | Copernicus licence - free, commercial use permitted, attribution required |
| Copernicus Climate Change Service (C3S) - ERA5 | Historical weather back to 1940, powering our "on this day" and climate pages | Copernicus licence |
Neither the European Commission nor ECMWF is responsible for any use of the Copernicus information contained here.
| SOURCE | WHAT WE USE | LICENCE |
|---|---|---|
| GeoNames | The gazetteer behind every town and city page on this site - names, coordinates, timezones, population | CC BY 4.0 |
| DB-IP | IP Geolocation by DB-IP - City Lite database, used to show your local weather on arrival | CC BY 4.0 |
| Copernicus DEM | Elevation data | Copernicus licence |
| PROJECT | ROLE | LICENCE |
|---|---|---|
| Open-Meteo | The forecast engine and processed model database, run unmodified as a separate service alongside our own API | Code AGPL-3.0; data CC BY 4.0 |
| MapLibre GL JS | Map renderer on our weather map | BSD 3-Clause |
| OpenFreeMap · OpenMapTiles · OpenStreetMap | Base map tiles and the underlying map data - © OpenStreetMap contributors | ODbL |
| Figtree | The typeface you're reading | SIL Open Font License 1.1 |
If we've credited a source incorrectly, missed one, or you maintain a dataset listed here and want the wording changed, write to and we'll fix it.