Collaborative Research: A Polarimetric Radar Climatology of Supercell Thunderstorms in the United States

Tornado warning lead times and false alarm rates have not improved significantly in recent years. The researchers funded under this award will use upgraded weather radar technology to determine if there are certain signals in the data that can be used to help improve understanding and forecasting of tornado development. The main societal impact of the work is related to public safety, through enhanced understanding and improved data to help operational forecasters provide warnings to the public. Students will also be trained in the latest methods, helping to provide a highly capable workforce. The National Weather Service completed their upgrade of the nation's weather radar system to dual-polarization capability in 2013, and since that point data has been collected on thousands of supercell thunderstorms. The research team plans to exploit this resource by developing a climatology of radar characteristics of supercell thunderstorms. The goal of the project is to establish definitive relationships between polarimetric variables and supercell characteristics, structure, and evolution. Automated methods will be used to select around 1000 cases that can be used to identify links among distinct polarimetric radar markers, supercell evolution, and near-storm environment parameters. The specific scientific objectives of the project are to: 1) distinguish between tornadic and non-tornadic supercells by identifying microphysical differences between the two sets, 2) compare polarimetric radar signatures and estimated drop size distributions to the near storm environment, and 3) determine how polarimetric signatures and estimated drop size distributions change during important storm processes. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.