February Flash Flood Drenches Tampa Bay (Index)
Figure 1. Precipitation Accumulation Estimate, Florida Peninsula, 7 AM EST February 3rd to 7 AM EST February 4th, 2006. (click to enlarge)	Figure 2. Rainfall across Pinellas and Hillsborough Counties, February 3rd and February 4th, 2006, from surface observers (click to enlarge).
Water Rescues, Property Damage in Pinellas After nearly a foot of rain falls
The combination of tropical moisture flowing into a line of thunderstorms with an approaching upper level disturbance, along with smaller scale features to be investigated, allowed a train of intense thunderstorms to repeatedly hammer portions of the Tampa Bay area on February 3rd. When all was said and done, between 8 and more than 11 inches of rain fell in roughly a five hour period in a stripe extending from Pinellas Park northeast through Lealman and Feather Sound, then across Old Tampa Bay to west Tampa, including Tampa International Airport.The area of heaviest rain was so concentrated that downtown St. Petersburg, less than 10 miles away, recorded less than an inch of rain during the same period! The daily record was shattered at Tampa; in fact, the total of 8.29 inches ranked unofficially as the 4th wettest calendar day since 1890. A preliminary rainfall summary for the heart of the event (February 3) can be found here.The torrential rains caused flash flooding in the areas where more than 8 inches fell. The flash flooding prompted the mayor of St. Petersburg to term the event a "hundred year flood". In Lealman, an entire mobile home community was evacuated, and at least 60 of the homes were flooded. Several roof collapses were reported, including a box store in north St. Petersburg and another at a community center in Treasure Island. Hundreds of vehicles were stranded by the flood waters; total damage to property will likely be in the millions. The system began quietly enough; 12 hours prior to the event, convection was just beginning to organize well south of Panama City. The event was indirectly associated with an approaching cold front.	A little after midnight, a few strong storms began moving toward the Big Bend region of Florida. As those moved inland and weakened, others began to form in a line, or "train", farther southwest in the still unstable air mass.Outflow boundaries from the developing line soon formed a cluster of storms well ahead of it, moving onshore in Citrus County. Soon, the entire system formed a line of storms which extended from Marion County through Citrus County and into the Gulf.This line would remain nearly stationary through the pre-dawn hours of the 3rd, dumping a radar estimated 3 to 4 inches of rain in Citrus County. An event that initially had the earmarks of a severe weather episode was transitioning into a heavy rainfall situation as well. By daybreak, new cells were forming in the Gulf west and northwest of the Tampa Bay metropolitan area, likely fed by strong southerly inflow of warm humid air. Sarasota/Bradenton airport reported temperatures of 76 or higher through the early morning, with dewpoints near 70 and sustained south winds in excess of 20 mph.Shortly after sunrise, thunderstorms began impacting the immediate Tampa Bay metropolitan area, and by mid morning the strongest cells were developing over central Pinellas County. Unlike overnight, when the "train" of thunderstorms propagated south, the line stalled, and additional cells containing torrential rains and frequent cloud to ground lightning continued to affect the area from central Pinellas County northeast through west Tampa toward Busch Gardens. So, why did the line stall? There may be many reasons, from the affects of inflow up Tampa Bay to the approach of an upper level disturbance which "lifted" the line back north. Check back soon for a full report!