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Home > GFS half degree documentation

The Global Forecast System (GFS) model was originally developed by J. Sela (Sela 1982, 1988), and is continuously improved by the Global Climate and Weather Modeling Branch which conducts a program of research and development in support of the Environmental Modeling Center ( of the National Centers for Environmental Prediction (NCEP operational forecasting mission for global prediction for medium range (3-14 days) and for extended range (week2 S/I) is at The operational GFS consists of the final Global Data Assimilation System, the GFS forecasts, and the Ensemble forecasts (ENS). The GFS is a consolidation of the forecasts formerly known as the Aviation (AVN) and the Medium Range Forecast (MRF). The model is based on the usual expressions of conservation of mass, momentum, energy, moisture with T382 truncation, about a .3 degree physics (Gaussian) grid and 64 levels in a hybrid sigma-pressure vertical coordinate. Output is posted to a 0.5 degree equally spaced in longitude/latitude with 3-h forecast interval to 180-h, cycled 4X/day, with 47 vertical standard pressure levels called the "GFS 0.5 degree" data set in NOMADS. See History of recent modifications to the global forecast/analysis system at: The model performance statstiscal web page is: More technical information can be found in the Parallel runs home page: Documentation homepage: Source code at:


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