Validation of Z-R relationships for Central Florida thunderstorms

During the summer of 2010, rain gauges were deployed ahead of storms throughout Central Florida. The goal of this project was to gain a better understanding of radar reflectivity (Z) and rainfall rates (R), better known as a Z-R relationship, in the region. Rainfall rates were calculated using data retrieved from a Davis weather station, and reflectivity data was obtained from the NEXRAD Information Distribution Service (NIDS). Large departures were documented between observed rainfall rates and the expected values based on the National Weather Service's Z-R relationship (Z=300R^1.4) used for summertime convective storms. The dependency of the rainfall rate departures on various meteorological parameters were statistically analyzed using ANOVA. The results showed that the no single parameter could significantly (P < 0.05) explain the deviations observed, though the wind speed and the distance from the radar were found to be more significant than the humidity or dew point parameters.