Radar Diagnostic Parameters as Indicators of Severe Weather in Central Florida

摘要

Diagnostic techniques based on WSR-88D radar observations and sounding data are needed to assess severe storm potential in Florida's semi-tropical thunderstorm environment. To begin this effort, nearly 100 severe weather events involving hail 3/4 in (1.9 cm) or greater in diameter, thunderstorm wind gusts 50 kt (26 m/s) or greater, or tornadoes were examined, along with RADAP II reflectivity and VIL (Vertically Integrated Liquid) observations. RADAP II algorithms are similar to those which will be employed with the WSR-88Ds. Several other parameters, including (1) cell density (VIL divided by echo top), (2) cell momentum (VIL (mass per unit area) multiplied by storm velocity produces a quantity proportional to momentum and will be referred to as momentum for the study), and (3) echo top growth rates were calculated for comparison with severe storm reports. In addition, a formula for hail detection was derived to represent processes responsible for different types of severe weather. Tornadoes are classified by the method of formation as stretched vortex, gust induced or dynamic. Severe wind gusts are classified primarily by the time of year in which they occur. Results from the study could be integrated into WSR-88D severe weather algorithms designed more specifically for the Florida environment.