Data reference

NOAA data sources reference

NOAA operates the largest free public weather dataset in the world. Here is what is available, where to find it, and what each product is actually good for.

Real-time forecast models

GFS (Global Forecast System)

13 km global model. Runs every 6 hrs, forecasts to 16 days. Best for medium-range planning.

HRRR (High-Resolution Rapid Refresh)

3 km CONUS convection-allowing. Runs hourly, 18-48 hr forecast. Best for convection prediction.

RAP (Rapid Refresh)

13 km CONUS. Runs hourly. Data assimilation is fast, good for near-term.

NAM (North American Mesoscale)

12 km CONUS + 3 km nest. Runs every 6 hrs. Alternative to GFS for CONUS.

SREF (Short-Range Ensemble)

Ensemble of NAM and RAP. Uncertainty quantification.

GEFS (Global Ensemble)

31-member GFS ensemble. Long-range probabilistic.

Radar data

NEXRAD (Level 2) — raw radar data. Available from AWS S3 (noaa-nexrad-level2 bucket).
NEXRAD (Level 3) — processed products. Available from AWS and NOAA NCEI.
MRMS — Multi-Radar Multi-Sensor. Merged national radar mosaic.
TDWR — Terminal Doppler at airports. Higher resolution near airports.
Historic radar — NCEI archive back to 1991.

Satellite data

GOES-East (GOES-16) — geostationary at 75°W, covers Americas.
GOES-West (GOES-18) — geostationary at 137°W, covers western hemisphere.
NOAA-20 and NOAA-21 — polar orbiters. Global coverage twice daily.
Suomi NPP — polar orbiter with VIIRS.
Access: AWS S3 (noaa-goes16 bucket), NASA Worldview.

Historical archives

NCEI (National Centers for Environmental Information) — the archive for climate data.
ISD (Integrated Surface Database) — hourly station data back to 1901.
GHCN (Global Historical Climatology Network) — daily station data back to 1800s.
SPC Storm Reports — every filed severe weather report since 1950.
NCEI Storm Events Database — tornado, hail, wind, and flood data by county since 1950.

Ocean and buoy data

NDBC (National Data Buoy Center) — hundreds of ocean and Great Lakes buoys.
C-MAN stations — coastal marine automated network.
Tides and Currents — 200+ tidal stations.
NHC hurricane track archive — every hurricane since 1851.

Upper-air data

RAOB (Radiosonde Observations) — 92 US launch sites, twice daily.
Wyoming Sounding Archive — university.wyoming.edu upperair archive.
NCEI Radiosonde Archive — full historical soundings.

APIs and access

api.weather.gov — official NWS API. Free, no key required.
NOMADS — real-time model output.
THREDDS servers — model data via OPeNDAP.
AWS Open Data — s3://noaa-* buckets, no charge.
NCEI FTP/HTTPS — historical archives.
USCRN — Climate Reference Network stations.