NCEP Numerical Forecast/Analysis Systems

This animated precipitation map above an example of a 6 day interval from a run of the Global Forecast System (GFS).

Data from the NCEP numerical guidance systems listed below are available through NOAA's National Operational Model Archive and Distribution System (NOMADS).

  • Global Forecasting System
    The Global Forecast System (GFS) is the cornerstone of NCEP's suite of numerical ... guidance, providing forecasts at 13 km resolution to 10 days and 55 km resolution for days 10-16. The GFS is used for initial and/or boundary conditions for other NCEP systems for regional, ocean and wave prediction.   Show more >
  • Global Ensemble Forecast System
    The GEFS is NCEP's 21-member global ensemble prediction system using the NCEP Glo... bal Model, running to 8 days at 33 km resolution and from days 8-16 at 55 km. Initial perturbations are created with an Ensemble Kalman Filter scheme, and stochastic physics schemes are used to represent model error.   Show more >
  • NCEP Data Assimilation
    The NCEP hybrid ensemble data assimilation system with the Grid-Point Statistical...  interpolation (GSI) analysis is used to generate initial conditions for NWS operational global, regional, mesoscale, rapid refresh, Real-Time Mesoscale Analysis (RTMA) and hurricane guidance systems.   Show more >
  • Climate Forecast System
    Climate Forecast System (CFS) is a fully-coupled global model that simulates the ... interaction between the Earth's atmosphere, oceans, land and sea ice. CFS provides forecasts out to nine months.   Show more >
  • North American Mesoscale
    The North American Mesoscale Model (NAM) is a regional weather forecast model cov... ering North America at 12 km horizontal resolution, with nested 3 km domains over the CONUS, Alaska, Puerto Rico, and Hawaii. It uses the NEMS version of the Non-Hydrostatic Meso Model on B-grid (NMMB)   Show more >
  • Rapid Refresh
    The Rapid Refresh is an hourly-updated assimilation/modeling system operational a... t NCEP, developed at NOAA's Earth Systems Research Laboratory. The RAP covers North America and is complemented by the High-Resolution Rapid Refresh (HRRR) system   Show more >
  • High-Resolution Rapid Refresh
    The HRRR is a 3-km resolution, hourly updated, convection-allowing forecast syste... m, developed by NOAA's Earth System Research Laboratory. Radar data is assimilated in the HRRR every 15 minutes over a 1-hour period adding further detail to that provided by the 13km Rapid Refresh system.   Show more >
  • Short-range Ensemble Forecast
    SREF has 26 members (13 WRF-ARW,13 NMMB) generated from a diverse set of analyses... /model physics at 16km resolution over North America, made 4 times/day to 87h. The products include ensemble max/min/median/mean, spread, and probability, and are available in raw, bias-corrected, or downscaled format.   Show more >
  • High-Resolution Ensemble Forecast
    The High-Resolution Ensemble Forecast system employs NCEP's operational convectio... n-allowing (~3km) systems to generate ensemble products, using current/time-lagged forecasts from the HiresWindow run (ARW/NMMB over CONUS, Alaska, Hawaii, Puerto Rico). For the CONUS, the NAM 3km nest is also used.   Show more >
  • Global Real-Time Ocean Forecast System
    The Real-Time Ocean Forecast System (Global RTOFS) is based on an eddy-resolving ... version of the HYCOM (HYbrid Coordinates Ocean Model) at 1/12į degree resolution, run once/day at 00z. Each run starts with 48-h of hindcasting and produces full-volume forecasts from the initial time out to 8 days.   Show more >
  • HWRF
    The NCEP Hurricane WRF (HWRF) system is one of the two on-demand hurricane models...  run at NCEP. HWRF uses the WRF version of the Non-Hydrostatic Mesoscale Model (WRF-NMM), and is coupled to the Princeton Ocean Model.   Show more >
  • HMON
    HMON (Hurricanes in a Multi-scale Ocean-coupled Non-hydrostatic Model) is one of ... the two on-demand hurricane forecast systems run at NCEP. HMON uses the Non-hydrostatic Multi-scale Model on a B grid (NMMB) dynamic core. It includes vortex relocation, but has no data assimilation.   Show more >
  • NCEP Sea Ice Analysis
    NCEP's Sea Ice team works on sea ice analysis from satellite, sea ice modeling, a... nd ice-atmosphere-ocean coupling. Our work supports the Alaska Region of the National Weather Service, the Great Lakes Marine Forecasting group in the Cleveland NWSFO, and NCEP Numerical Modeling Systems.   Show more >
    The Real-Time Mesoscale Analysis (RTMA), UnRestricted Mesoscale Analysis (URMA) a... nd the Real Time Mesoscale Analysis with Rapid Updates (RTMA-RU) provides 15-min to 1-h surface analyses at 2.5-3 km resolution for the CONUS, Alaska, Hawaii, Puerto Rico, and Guam.   Show more >
  • NCEP Sea Surface Temperature Analysis
    NCEP has developed two different SST analyses: RTG -- Real Time Global, and the O... I -- Optimal Interpolation. The RTG analyses are aimed at weather prediction and modeling, particularly at high resolution. The lower-resolution OI analyses are more for long range climate simulations.   Show more >
  • NCEP Air Quality Model
    The NOAA National Air Quality Forecast Capability (NAQFC) provides 2 day forecast... s of ozone and fine particulate matter surface concentration from 06 and 12 UTC from the EPA Community Model for Air Quality (CMAQ). Predictions are made over the CONUS, Alaska, and Hawaii.   Show more >
  • NEMS GFS Aerosol Component
    The NEMS GFS Aerosol Component (NGAC) is a global in-line aerosol forecast system... ; the forecast component is the GFS; the aerosol component is the Goddard Chemistry Aerosol Radiation and Transport Model (GOCART). It makes 120-h forecasts of dust, sea salt, sulfate, and carbonaceous aerosols.   Show more >
  • N.American Land Data Assimilation System
    The NLDAS runs uncoupled land-surface models driven by NAM atmospheric forcing an... d observed surface data. In NCEP Production it runs in near-real-time, and was run off-line in a 30-year retrospective. It generates hourly surface forcing and simulation of surface energy fluxes.   Show more >
  • Nearshore Wave Prediction System
    The Nearshore Wave Prediction System (NWPS) provides on-demand, high-resolution n... earshore wave model guidance to U.S. coastal WFOs, triggered in real time by forecast wind grids prepared and submitted by the individual offices.   Show more >
  • North American Ensemble Forecast System
    A joint project involving the Meteorological Service of Canada (MSC) in Canada, t... he National Weather Service (NWS) in the United States, and the National Meteorological Service of Mexico (NMSM) in Mexico providing numerical weather prediction ensemble guidance out to 16 days.   Show more >
  • Great Lakes Wave Model (WAVEWATCH III)
    The NCEP Great Lakes Wave production system runs the WAVEWATCH III model, forced ... with atmospheric data from NCEPís North American Mesoscale Model (NAM) and the National Digital Forecast Database (NDFD)   Show more >