NOAA REFS

The RRFS Ensemble Forecast System (REFS) is a National Oceanic and Atmospheric Administration (NOAA) National Centers for Environmental Prediction (NCEP) ensemble product system. It produces ensemble products on a 3 km grid, including means, spreads and probabilities of exceeding thresholds, from the current and 6 hour old cycles of the deterministic Rapid Refresh Forecast System (RRFS) and its ensemble (RRFS ENS), plus two HRRR members over the continental United States.

NOAA REFS is pre-operational, so expect changes to the model data and to the structure of this dataset.

dynamical.org republishes NOAA REFS as free, analysis-ready Icechunk Zarr archives — open them directly with Xarray, no GRIB wrangling or bulk downloads.

Forecasts

• NOAA REFS forecast, hourly, virtualnoaa-refs-forecast-hourly-virtual
  map-optimized · low-latency
  CONUS · all variables · 3 km
• NOAA REFS forecast, 3 hourly, virtualnoaa-refs-forecast-3-hourly-virtual
  map-optimized · low-latency
  CONUS · all variables · 3 km

Data access

• STAC catalog (browse) — the machine-readable source of truth.
• AWS Open Data Registry entry · browse the S3 bucket