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Numerical Weather Prediction
The following NWP data, and data assimilation data (input observational weather data), are available through NOAA's National Operational Model Archive and Distribution System (NOMADS).
Global Data Assimilation System (GDAS)
GDAS is the set of assimilation data, both input and output, in various formats for the Global Forecast System model, which has been archived since 2004.
Global Ensemble Forecast System (GEFS)
GEFS is a global-coverage weather forecast model made up of 21 separate forecasts, or ensemble members, used to quantify the amount of uncertainty in a forecast. GEFS is produced four times a day with weather forecasts going out to 16 days.
Global Forecast System (GFS)
The GFS model is a coupled weather forecast model, composed of four separate models that work together to provide an accurate picture of weather conditions. The entire globe is covered by the GFS down to a horizontal resolution of 28 km.
North American Mesoscale (NAM)
NAM is a regional weather forecast model covering North America down to a horizontal resolution of 12 km. Dozens of weather parameters are available from the NAM grids, from temperature and precipitation to lightning and turbulent kinetic energy.
Rapid Refresh (RAP)
RAP is a regional weather forecast model of North America with separate sub-grids (with different horizontal resolutions) within the overall North America domain. RAP forecasts are generated every hour with forecast lengths going out 18 hours.
Rapid Update Cycle (RUC)
RUC is a regional weather forecast model of the continental United States with forecast lengths going out 12 hours. RUC data are no longer produced operationally by the National Centers for Environmental Prediction (NCEP).