Gridded Model Forecast Data ( GRIB ) is available on Skytap. Data is delivered in WMO GRIB Edition 1 format.
Each computer forecast "GRIB" model is unique, and may be “run” by the owner agency (NCEP, NWS, etc) one or more times per day. Each time they run the model, it will generate data for one or more forecast hours ( taus ), which will contain one or more parameters, such as Pressure or Temperature at multiple atmospheric levels.
There are hundreds of possible parameters defined by the WMO, and each national agency may define additional parameters specific to their models.
To further complicate matters, these forecasts are produced for specific geographic coverages, called “grids”. Each grid defines a number of points in X and Y axis cooresponding to a geographic map projection.
Fortunately for the user, Marta’s Yosemite software takes care of a lot of these details for you. As a Skytap user, you simply request GRIB data by specifying the Model and Parameter. Skytap delivers all forecast hours at all atmospheric levels in all grids for each requested item. When Yosemite displays the data, it automatically picks the grid that fits best into your area of interest.
The available GRIB models data sets are tabulated in real-time on the Skytap GRIB INVENTORY page.