THE STORM CELL IDENTIFICATION AND TRACKING ALGORITHM - AN ENHANCED WSR-88D ALGORITHM

Accurate storm identification and tracking are basic and essential par ts of radar and severe weather warning operations in today's operation al meteorological community. Improvements over the original WSR-88D st orm series algorithm have been made with the Storm Cell Identification and Tracking algorithm (SCIT). This paper discusses the SCIT algorith m, a centroid tracking algorithm with improved methods of identifying storms (both isolated and clustered or line storms). In an analysis of 6561 storm cells, the SCIT algorithm correctly identified 68% of all cells with maximum reflectivities over 40 dBZ and 96% of all cells wit h maximum reflectivities of 50 dBZ or greater. The WSR-88D storm serie s algorithm performed at 24% and 41%, respectively, for the same datas et. With better identification performance, the potential exists for b etter and more accurate tracking information. The SCIT algorithm track ed greater than 90% of all storm cells correctly. The algorithm techni ques and results of a detailed performance evaluation are presented. T his algorithm was included in the WSR-88D Build 9.0 of the Radar Produ cts Generator software during late 1996 and early 1997. It is hoped th at this paper will give new users of the algorithm sufficient backgrou nd information to use the algorithm with confidence.