Using grid-based forecast verification to promote improved service in NWS/Western Region

National Weather Service (NWS) Western Region (WR) has embarked on a multi-year project to examine the performance of grid-based forecasts. The accuracy of model and NWS temperature forecasts has been examined using BOIVerify, a new application that compares grid-based forecasts to an objective analysis. The analyses used in this study incorporate thousands of surface mesonet observations from MesoWest.

Similar weather patterns from the 2006/07 winter season were grouped in order to quantify the accuracy of forecast data under various regimes. Some regimes contained enough cases to produce statistically significant results that could have ramifications on the evolution of the NWS forecast process. This project is the start of an objective process to distinguish when and where forecasters should rely on model guidance to improve NWS forecasts. The goal of the program is to improve forecasts and reduce routine workload through adoption of forecast methodologies that were scientifically validated using verification data.