12/2/2009 FCST: VA, NC, SC, GA, FL

Feb 14, 2005
Charleston, South Carolina
Impressive developing 500mb trough should become negatively tilted, w/ >80 kt. winds over GA by 00z Wednesday. A good southeasterly fetch of gulfstream moisture will bring aoa 65td dewpoints over a broad swath of the eastern Carolinas. With sufficient low-level CAPE and strong wind fields, veering w/ height (southwesterly 500mb @ 70 kt, southerly 850's @ 65 kt, southeasterly surface winds @20) could very well set up favorable conditions for a significant bout of severe weather from the Savannah River basin, up along and east of the I-95 corridor to Lumberton, NC. Later Wednesday night, the LLJ may keep feeding the system and result in some noctural events further north along the North Carolina coast. LCL's should be well under 500 meters; I just like the overall low-level nature of this setup, which is quite consistent with cold season, nocturnal tornado events in this part of the country.

Moisture advection to the target area will likely begin later this afternoon, which doesn't leave alot of time before the rapid approach of the upper air dynamics. However, once advection begins it should crank in earnest and, after all, doesn't have a great deal of mileage to traverse. SB CAPE across eastern SC may only reach 500 to 1,000 j/kg, but again, the combination of low level instability and helicity values would certainly support some rotating updrafts.

What caught my eye was how the SPC picked up on this setup so definitively on its Day 3 outlook yesterday, and today I notice a broad hatched area and the local (Charleston) AFD is even talking about strong and possibly long-track tornadoes.

For an "off season" setup, this one definitely bears keeping an eye on.
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