AFGWC Macro-Scale Update Forecast Model.
Abstract
The Air Force Global Weather Central (AFGWA) macro-scale update forecast model is specifically designed to be compatible with the macro-scale baroclinic prediction model, which produces forecasts of height, wind, and temperature at six levels (850, 700, 500, 300, 200, and 100 mb) for an octagonal (hemispheric) grid. The update model produces six to 36 hour updated forecasts for window areas of 15x15 to 35x35 grid points (381 km spacing) which may be located anywhere within the octagon. The model is employed whenever required to update areas of the hemispheric forecasts which were initally data-deficient so as to significantly degrade the forecast. Stream functions are forecast at six levels and are used as input to solve the diagnostic omega equation, from which vertical velocities are obtained for solution of the vorticity equation for a new stream function tendency. The time step is 45 minutes. Horizontal boundary conditions are determined from the hemispheric forecasts being updated. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1971
- Accession Number
- AD0735742
Entities
People
- James Kerlin