Development of Processing Software for the Global Theater Weather Analysis and Prediction System (GTWAPS)

The Air Force Weather Agency (AFWA) provides fine scale models of the atmosphere in support of military operations and other national programs. To perform this task, AFWA uses The Pennsylvannia State University/National Center for Atmospheric Research (PSU/NCAR) Mesoscale Model version 5 (MM5). The MM5 produces a number of model state parameters in a unique format. Three-dimensional data exists on the models native sigma coordinate. To make use of the MM5 output the GTWAPS prototype program developed an application called MMPOST. MMPOST reads the MM5 data, derives additional meteorological parameters, interpolates data to isobaric and altitude levels, and outputs the data in the native format of the Vis5d visualization tool and in GRIB format for transmission.

The GTWAPS program is now developing a second generation generic post processor (GENPOST) to ingest any data in GRIB format, derive additional user selected parameters, and output them in GRIB format. The program will replace MMPOST at user sites to produce a complete set of derived parameters from MM5 data converted to GRIB by MMLITE. It can also derive global parameters from other input data in GRIB format. This enables GENPOST to produce data with global coverage and extended forecast times from input such as the AVN or NOGAPS models. This ability will also enable forecasters at remote sites to derive additional parameters from foreign meteorological models.