Strong Storms Soon

The Storm Prediction Center is considering a Severe Thunderstorm Watch for parts of Tennesee, Alabama, Mississippi, and Arkansas. The remnants of overnight storms in Arkansas and an upper-air disturbance will work on a hot, humid air mass over the South this afternoon, and that could mean some isolated strong and severe storms with gusty winds, hail, torrential rain, and frequent lightning. Here’s the graphic and discussion from SPC:

MESOSCALE DISCUSSION 1229
NWS STORM PREDICTION CENTER NORMAN OK
1054 AM CDT WED JUN 15 2011

AREAS AFFECTED…FAR ERN AR/SERN MO INTO SRN KY…MUCH OF TN…NRN
MS AND AL

CONCERNING…SEVERE POTENTIAL…WATCH LIKELY

VALID 151554Z – 151800Z

STORMS SHOULD INCREASE OVER THE NEXT FEW HOURS…AND A WATCH IS
LIKELY FOR DAMAGING WINDS AND LARGE HAIL.

SURFACE MAP SHOWS LOW PRESSURE TROUGH ROUGHLY ALONG THE MS RIVER AND
TRAILING SWWD ACROSS AR. MORNING CONVECTION FORCED BY WARM ADVECTION
WAS QUICKLY MOVING EWD ACROSS THE OH/TN VALLEYS ALLOWING FOR RAPID
DESTABILIZATION BEHIND. TEMPERATURES WERE ALREADY INTO THE UPPER 80S
WITH DEWPOINTS IN THE LOWER 70S F AT 16Z. FURTHER…MORNING
SOUNDINGS SHOWED IMPRESSIVE MID LEVEL LAPSE RATES ON THE ORDER OF
7.5 – 8.0 C/KM WHICH WILL RESULT IN STRONG INSTABILITY.

CAPPING SHOULD BE REMOVED OVER THE NEXT FEW HOURS WITH SEVERAL
CLUSTERS OF STORMS FORMING WITH WEAKLY CONVERGENT LOW LEVEL FLOW.
40-50 KT MID LEVEL FLOW WILL SUPPORT STORM ORGANIZATION WITH TIME.
GIVEN HIGH PRECIPITABLE WATER…STEEP LAPSE RATES AND THE
PROBABILITY OF HAIL LOADED DOWNDRAFTS…DAMAGING DOWNBURSTS ARE
LIKELY.

..JEWELL.. 06/15/2011

-Jason
Follow me on Twitter: @simpson3340
On Facebook: Jason Michael Simpson

Category: Alabama's Weather, Severe Weather