P67 Investigating seasonal and regional differences of surface drag parameterization schemes available in WRF

Harrold, Michelle, National Center for Atmospheric Research (NCAR), Hongli Jiang, Cooperative Institute for Research in Environmental Sciences, and Jamie Wolff, NCAR

The Weather Research and Forecasting (WRF) model is a highly-configurable, state-of-the-art numerical weather prediction system used in both research and operational forecasting applications. Due to the broad spectrum of forecast needs of the WRF user community, it is necessary to rigorously test select model configurations in order to evaluate the performance for specific applications. The Developmental Testbed Center (DTC) extensively tested the Advanced Research WRF (ARW) dynamic core with a physics suite that is currently being using in the High-Resolution Window (HIRESW) Forecast System at the National Centers for Environmental Prediction (NCEP). The testing consisted of running three configurations with the HIRESW physics suite; the only difference in the configurations was the topo_wind namelist option. One configuration, which was used as the baseline, set topo_wind = 0, the second set topo_wind = 1, and the third set topo_wind = 2. Testing was conducted over the Contiguous United States, with a 15-km parent domain and a 5-km nest. The evaluation includes a forecast period from 1 July 2011 to 29 June 2012, with forecasts being initialized every 36 hours; this extensive testing period allows for robust results as well as the ability to investigate performance spatially and temporally. This presentation will focus primarily on the results from the baseline configuration, and the evaluation will include traditional verification metrics for surface and upper air variables. The impact of topo_wind options on surface winds will be the primary focus of a companion presentation.