Mesoscale Elements of the December 14, 2006 West Palm Beach Flash Flood

Mesoscale features combined with an uncharacteristically moist atmosphere for mid-December resulting in a record 8.22" rain event in West Palm Beach, FL, on 14 December 2006. This occurred in the absence of salient synoptic-scale features. A mesolow, along with several mesoscale boundaries combined with Precipitable Water values over 2 Standard Deviations above normal to produce widespread 4-6" of rain, with locally higher amounts, and flash flooding in the vicinity of the West Palm Beach International Airport. The meso-Ą scale features exhibited relationships to the Maddox frontal-type flash flood model originally; however with persistent convective development leading to meso-high formation, elements of Maddox' conceptual meso-high model were exhibited later as well. This paper presents an evaluation of the environmental and model data leading to the flood event.