WSI's Operational Implementation of the WRF model

WSI Corporation has developed a real-time, national modeling system that uses the Weather Research and Forecast model (WRF) as the forecast engine. Forecasters at WSI have been using output from WRF as guidance in producing forecasts for clients since April 2004. Distribution of WRF-based products to media clients will begin in the 2nd quarter of 2005. WRF is proving that it can generate physically realistic fine-scale structure not seen in the available output resolutions of other operational forecast models. Forecasts are run every 3 hours at 12 km grid spacing with a domain covering the continental United States. Forecasts are run out to 51 hours, with output every 30 minutes. Model runs complete about 2 hours after the initialization time.

The operational WRF configuration was chosen to minimize errors in short-term convective weather forecasts. Selection of the configuration was based on results from a series of more than 4000 simulated forecasts over the central Plains of the United States during an active severe weather season (April/May 2003).

WRF output has been fully integrated within WSI's suite of media applications. Broadcast quality graphics from current simulations as well as from simulations of hurricanes affecting Florida during the 2004 hurricane season will be presented.

Additionally, output from WRF simulations is used in several post-processing algorithms that WSI has developed to forecast precipitation-type, snowfall accumulation, convective weather parameters (hail size, lighting flash rate, convective wind gust potential, etc.), clear-air turbulence and an electrical power disruption index. Examples and verification of these post-processing algorithms will be presented as well.