Evaluation of a Hail Size Discrimination Algorithm for the Polarimetric WSR-88D

An initial Hail Size Discrimination Algorithm (HSDA) based upon cloud and polarimetric variable modeling was evaluated and modified using high resolution observations from the Severe Hazards Analysis and Verification Experiment (SHAVE). The HSDA runs within the Hydrometeor Classification Algorithm (HCA) to identify three different hail size classes: small (less than 25 mm in diameter), large (25 mm to 51 mm in diameter) and giant (greater than 51 mm in diameter). The new HSDA incorporated several new features to reduce false alarms and add spatial coherency to the hail size designations. Currently work is ongoing to better relate variable values and signatures above the melting level to surface hail sizes. This presentation will summarize the evaluation of the HSDA and highlight potential changes to the algorithm for better identification above the melting level.