Use of NEXRAD Rainfall Data to Develop Climatologically Homogenous Rain Areas for Central and South Florida

Climatologically homogeneous rainfall regions were developed for the South Florida Water Management District (District) using statistical techniques in conjunction with physical meteorological processes. Rain gauge adjusted NEXRAD (radar) derived rainfall datasets were prepared and stored in the Florida State University (FSU) MPE database. The variability in these data then were analyzed both spatially and temporally to determine rainfall processes and local rainfall patterns. Spatial averages and correlation maps were developed to identify regions that vary similarly in the amount and timing of rainfall. The spatial variability of the multi-sensor rainfall data was identified using daily data. The climatologically homogenous rain areas were derived for four seasons, namely, wet, dry and two transitional seasons. Homogenous rainfall regions were also developed for the annual scale. This paper will describe methodologies in detail and will present examples of the homogeneous areas, showing their locations and presenting their rainfall characteristics. It is believed that similar techniques could be used in other parts of Florida to identify areas having similar rainfall behavior. These approaches can be very useful in various hydrologic designs.