Evaluating the use of reflectivity heights for hail detection with high-resolution hail reports

National Weather Service forecasters use a variety of techniques to diagnose severe hail in thunderstorms. One technique is interrogating the radar reflectivity field and comparing the heights of certain reflectivity values to reference levels, such as the melting layer. Verification of these values and heights is difficult due to the time and space scales present in Storm Data and the fact Storm Data only contains reports of severe hail. Further the presence of no hail report in Storm Data for a particular storm is not necessarily confirmation that the storm did or did not produce severe hail. The National Severe Storms Laboratory has conducted the Severe Hazards Analysis and Verification Experiment (SHAVE) in order to collect high resolution hail reports, including reports of no hail and non-severe hail. This presentation will evaluate reflectivity values and the heights of those values relative to different reference heights. This presentation will also use the high resolution nature of the SHAVE reports by using a cone search method based on a storm's location and motion. This cone search method places the skill of the reflectivity heights in context of increasing lead time.