Convective Storms & NWP Seminar Series presents...
An Assessment of Convection-Allowing WRF-ARW Configurations: Utility as next day guidance and sensitivity to resolution and physical parameterizations
Craig Schwartz
The University of Oklahoma School of Meteorology
12 December 2008, 2:00 PM
National Weather Center, Room 5600
120 David L. Boren Blvd.
University of Oklahoma
Norman, OK
Directions to the NWC (.pdf, 60 kb)
During the 2007 NOAA Hazardous Weather Testbed (HWT) Spring Experiment, the Center for Analysis and Prediction of Storms (CAPS) at the University of Oklahoma produced daily convection-allowing (no cumulus parameterization) forecasts from a single deterministic 2 km model and a 10-member 4 km resolution ensemble. All models used the Advanced Research WRF (WRF-ARW) core and ran for 33 hours over a domain covering approximately three-fourths of the continental United States.
Output from these forecasts is examined to assess the utility of WRF-ARW models as next day guidance for forecasters of severe storms and heavy precipitation. Specifically, WRF-ARW sensitivity to horizontal resolution and physical parameterizations is discussed. Additionally, the WRF-ARW forecasts are shown to be of higher quality and greater value than forecasts from the operational “benchmark” 12 km North American Mesoscale (NAM) model. Finally, a post-processing technique employing a “neighborhood” approach is discussed and applied to the ensemble.
The findings raise important questions regarding real-time, high-resolution, large domain model simulations and have implications for both model developers and operational meteorologists.