SPC AC 071254
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0654 AM CST FRI MAR 07 2008
VALID 071300Z - 081200Z
...THERE IS A SLGT RISK OF SVR TSTMS SOUTHEAST INTO THE SRN/MID
ATLANTIC...
...SOUTHEAST INTO THE COASTAL CAROLINAS/SERN VA...
LEADING MID LEVEL IMPULSE NOW OVER THE CENTRAL GULF COAST STATES
WILL WEAKEN AND EJECT RAPIDLY NEWD TODAY AS STRONGER IMPULSE
AMPLIFIES LONGWAVE TROUGH INTO THE LOWER MS RIVER VALLEY. LLJ IS
ALREADY QUITE ESTABLISHED OVER NRN FL INTO SERN GA /50+ KT 1 KM AND
ABOVE/ WHICH WILL LIFT NWD ACROSS THE ERN CAROLINAS TODAY...WHILE
H85 WINDS SLOWLY VEER TO WSWLY BUT REMAIN STRONG OVER FL THIS
AFTERNOON. SURFACE LOW NOW OVER SERN AL IS FORECAST TO DEVELOP NEWD
ACROSS CENTRAL SC/NC AND INTO SERN VA THROUGH 00Z...ALONG
STATIONARY/WEDGE FRONT EXPECTED TO REMAIN ESTABLISHED THIS
AFTERNOON.
...FL/SERN GA...
ONGOING QLCS IS EXPECTED TO RACE ENEWD ACROSS NRN FL/SRN GA THIS
MORNING /REFERENCE WW 104 AND ASSOCIATED SWOMCD/ AND POSSIBLY EXIT
THE SERN GA/NERN FL COAST AROUND 16-17Z. ALTHOUGH H85 FLOW WILL
GRADUALLY VEER THROUGH THE DAY...SURFACE WINDS WILL REMAIN SSWLY AND
MAINTAIN ENHANCED LOW LEVEL SHEAR AS AIR MASS BECOMES MODERATELY
UNSTABLE IN WAKE OF WARM FRONT NOW LIFTING NWD ACROSS CENTRAL FL.
12Z SOUNDING FROM TBW INDICATED STEEP MID LEVEL LAPSE RATES ARE IN
PLACE FURTHER ENHANCING INSTABILITY THIS AFTERNOON AHEAD OF STORMS
SPREADING EWD OFF THE GULF OF MEXICO...AS WELL AS WITH ANY ISOLATED
DEVELOPMENT INLAND. ACTIVITY WILL SPREAD ACROSS THE NRN HALF OF FL
EARLIER TODAY...AND MAY AWAIT STRONG UVV/S AND SURFACE FRONT BEFORE
ACTIVITY SPREADS ACROSS REMAINDER OF FL LATER TODAY/TONIGHT. GIVEN
STRENGTHENING DEEP LAYER SHEAR AHEAD OF MID/UPPER LEVEL
TROUGH...ENVIRONMENT WILL REMAIN QUITE FAVORABLE FOR SEVERE
THUNDERSTORMS IN THE FORM OF SUPERCELLS AND SMALL BOWING SEGMENTS.
TORNADOES AND DAMAGING WINDS ARE EXPECTED TO BE PRIMARY SEVERE
THREATS...ALTHOUGH STEEP LAPSE RATES AND MODERATE INSTABILITY WILL
ALSO SUPPORT LARGE HAIL. TORNADO/WIND THREAT COULD BE LOCALLY
ENHANCED BY E-W ORIENTED WARM FRONT/OUTFLOW FROM THIS MORNING/S
STORMS ACROSS CENTRAL FL TODAY...GIVEN EXPECTED DEGREE OF SHEAR AND
INSTABILITY. AN UPGRADE MAY BE WARRANTED IN LATER OUTLOOKS.
...ERN GA INTO CAROLINAS/SERN VA...
MORE QUESTIONS EXIST CONCERNING SEVERE POTENTIAL FARTHER NORTH INTO
THE CAROLINAS. HODOGRAPHS ARE CERTAINLY EXPECTED TO BECOME QUITE
FAVORABLE FOR WIND DAMAGE/TORNADO POTENTIAL AS SURFACE LOW DEEPENS
LATER TONIGHT...AND LLJ LIFTS NEWD. IN ADDITION...AS UPSTREAM
TROUGH TAKES ON MORE OF A NEGATIVE TILT...UPPER FLOW WILL BECOME
INCREASINGLY DIFFLUENT. HOWEVER...BOUNDARY LAYER DESTABILIZATION
INLAND OF IMMEDIATE NORTH CAROLINA COASTAL AREAS PRIOR TO 08/09-12Z
IS HIGHLY UNCERTAIN...AS IS LOCATION OF CAD/WEDGE FRONT. ALTHOUGH
INSTABILITY ACROSS THIS REGION WILL REMAIN MODEST...EXTREME SHEAR
SUGGESTS STORMS SHOULD QUICKLY BECOME ORGANIZED WITH ENSUING SEVERE
THREAT MODULATED BY DEGREE/DEPTH OF STABLE BOUNDARY LAYER.
..EVANS/HURLBUT.. 03/07/2008
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z
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