Tuesday, June 26, 2012

As Debby Does Perry and Lamont: "Why tropical storm Debby is such a wet, sloppy slow poke"

Perry and Lamont are actually a bit east of the Wakulla County weather station with the highest reported rainfall, 12.99 inches in 12 hours and 25 inches total.*
From the Christian Science Monitor:
Like the guest who overstays her welcome, tropical storm Debby is inclined to just sit over the Florida panhandle – and dump more rain than any host could possibly absorb. How much longer will it stay?
For residents of Florida's panhandle and into southeastern Georgia, tropical storm Debby might as well be renamed Debby the Drencher....
...Debby's crawl across the northeastern Gulf can be traced to the storm moving through a kind of doldrums in winds at the altitudes that tend to steer tropical cyclones.

Debby found itself between two branches of the jet stream – the polar jet to the north and the subtropical jet to the south, explains Jeff Masters, director of meteorology with the online service
Weatherunderground.com. At the same time, Debby has been caught between two broad regions of high atmospheric pressure – one over the west-central US and the other over Puerto Rico and the island of Hispanola.

The relative positions of these key players – including Debby – left winds that otherwise might have moved the storm along in a very weak state. That left Debby to drift along the northern Gulf in slow motion.
Debby's position in the Gulf "brought up incredible amounts of tropical moisture," the NHC's Mr. Feltgen adds. Powerful updrafts hoisted that moist air into the storm to feed it. That led to the formation "of bands of just horrific rainfall," he says....MORE
The state record (#2 in the U.S.):  Yankeetown, northwestern Florida, 9/5/1950, 38.7" as the result of another damp tramp, Hurricane Easy.