Evaluation of Dual-Polarization Radar Signatures in Pulse-Type Thunderstorm Severe Wind Prediction

Pulse severe thunderstorms are common across the Southeastern United States during the warm season, and can be amongst the most difficult storm type to warn for due to their chaotic and volatile nature. In order to better identify pulse thunderstorms capable of producing severe winds, warning forecasters have primarily relied upon their evaluation of the vertical distribution of reflectivity features to help determine storm strength. The implementation of dual polarization on the WSR-88D has expanded the amount of data available for the warning forecaster to utilize, but gaps remain in the research with respect to specifically identifying features within the dual pol moments that can increase weather warning operator confidence in National Weather Service (NWS) offices. Most research thus far has been beneficial for hail detection, with little attention given to the detection of severe winds. In this study, further investigation is done into the usefulness of Dual-Pol moments in identifying pulse-type thunderstorms that produce severe winds within the Charleston, SC Weather Forecast Office area of responsibility. Numerous features were detected in both legacy and Dual-Pol products, and related to the amount of lead time that they may be able to afford a forecaster issuing a warning for severe winds at the surface. The end result of this study is a basic set of general guidelines and quantitative thresholds for easily identifiable features that can be utilized to increase forecaster confidence during warning operations.