The Weather Research and Forecasting (WRF) Model is a next-generation mesoscale numerical weather prediction system designed to serve both operational forecasting and atmospheric research needs. It features multiple dynamical cores, a 3-dimensional variational (3DVAR) data assimilation system, and a software architecture allowing for computational parallelism and system extensibility.
WRF is suitable for a broad spectrum of applications across scales ranging from meters to thousands of kilometers.

Link to website : http://www.mmm.ucar.edu/wrf/users/

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