Accuracy of the Dual-Polarization Radar Precipitation Estimation Product within the Nashville, Tennessee County Warning Area

The recent introduction of dual polarization radar base data and products at the National Weather Service office in Nashville, Tennessee, has shone a new light on precipitation analysis. The advantages of this new technology will continue to be realized in the next several years. To date, the new data and products have enabled forecasters to better analyze rainfall rate and precipitation type, and hence, overall storm structure. Forecasters expect a better determination of precisely where the heaviest rainfall is occurring, which will lead to improved flash flood forecasting.

This presentation will include the results of a comparison of the quality of the new dual-pol precipitation estimates to those from the legacy WSR-88D Doppler for some recent events in the NWS Nashville County Warning Area. Sampling issues will be discussed, as will comparisons between rainfall estimates and observations from the Community Collaborative Rain, Hail & Snow Network and cooperative observers. We hope this discussion of the strengths and weaknesses of the radar estimation product will result in improved storm-structure knowledge and operational flash flood forecasting.