A Description of the Advanced Research WRF Version 2

The development of the Weather Research and Forecasting WRF modeling system is a multiagency effort intended to provide a next-generation mesoscale forecast model and data assimilation system that will advance both the understanding and prediction of mesoscale weather and accelerate the transfer of research advances into operations. The model is being developed as a collaborative effort ort among the NCAR Mesoscale and Microscale Meteorology MMM Division, the National Oceanic and Atmospheric Administrations NOAA National Centers for Environmental Prediction NCEP and Forecast System Laboratory FSL, the Department of Defenses Air Force Weather Agency AFWA and Naval Research Laboratory NRL, the Center for Analysis and Prediction of Storms CAPS at the University of Oklahoma, and the Federal Aviation Administration FAA, along with the participation of a number of university scientists. The WRF model is designed to be a flexible, state-of-the-art, portable code that is an efficient in a massively parallel computing environment. A modular single-source code is maintained that can be configured for both research and operations. It offers numerous physics options, thus tapping into the experience of the broad modeling community. Advanced data assimilation systems are being developed and tested in tandem with the model. WRF is maintained and supported as a community model to facilitate wide use, particularly for research and teaching, in the university community. It is suitable for use in a broad spectrum of applications across scales ranging from meters to thousands of kilometers. Such applications include research and operational numerical weather prediction NWP, data assimilation and parameterized-physics research, downscaling climate simulations, driving air quality models, atmosphere-ocean coupling, and idealized simulations e.g boundary-layer eddies, convection, baroclinic waves.