SPC AC 241952
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0152 PM CST TUE NOV 24 2009
VALID 242000Z - 251200Z
...NO SVR TSTM AREAS FORECAST...
...IA/IL AND S TX AREAS THIS AFTERNOON/EVENING...
A FEW ELEVATED THUNDERSTORMS WILL PERSIST THROUGH THE AFTERNOON
/EVENING WITHIN THE WARM CONVEYOR BELT ASSOCIATED WITH THE MO/IA
CLOSED LOW BEFORE INSTABILITY DIMINISHES. FARTHER S...THE TRAILING
SURFACE COLD FRONT HAS MOVED OFF THE MIDDLE TX COAST AND WILL PASS
DEEP S TX IN THE NEXT FEW HOURS. IN THE MEANTIME... SCATTERED
THUNDERSTORMS CAN BE EXPECTED ACROSS THE LOWER RIO GRANDE VALLEY IN
THE MOIST PRE-FRONTAL ENVIRONMENT.
...CENTRAL/S FL THROUGH EARLY WEDNESDAY...
A FEW THUNDERSTORMS WILL CONTINUE TO FORM INVOF A STALLED FRONT
ACROSS CENTRAL FL THROUGH THE AFTERNOON. OVERNIGHT...THE POTENTIAL
FOR ORGANIZED STRONG STORMS WILL INCREASE SOME AS A SPEED MAX IN THE
SUBTROPICAL JET...AND A WEAK ASSOCIATED SURFACE WAVE ALONG THE
FRONT...MOVE OVER THE GULF AND APPROACH THE W COAST OF FL EARLY
WEDNESDAY. VERTICAL SHEAR PROFILES ARE FORECAST TO BECOME AT LEAST
MARGINALLY SUPPORTIVE OF SUPERCELLS...WITH THE POSSIBILITY OF
ROTATING STORMS EMBEDDED IN ONE OR MORE OF THE GULF CLUSTERS...AND
MORE DISCRETE CELLS IN THE MODIFYING AIR MASS ALONG THE FL E COAST.
THE OVERALL SEVERE THREAT...HOWEVER...WILL CONTINUE TO BE LIMITED BY
MODEST DEEP-LAYER SHEAR AND INSTABILITY.
..THOMPSON.. 11/24/2009
.PREV DISCUSSION... /ISSUED 1003 AM CST TUE NOV 24 2009/
...CNTRL/S FL...
SCTD MAINLY DIURNAL STORMS EXPECTED THIS AFTERNOON INVOF AND S OF
WEAK W-E FRONT LOCATED E/W CENTRAL FL PENINSULA...WHERE SBCAPE WILL
APPROACH 1000-1500 J/KG. RELATIVELY WEAK LOW TO
MID LVL SHEAR AND MODEST LAPSE RATES SHOULD PRECLUDE ANY SVR
THREAT TODAY. HOWEVER...ADDITIONAL STORMS MAY MOVE INTO/DEVELOP
ACROSS THE REGION LATE TONIGHT/EARLY WED AS WIND FIELD/WAA
STRENGTHEN AHEAD OF APPROACHING MID/HIGH LEVEL GULF IMPULSE.
COUPLED WITH BACKED LOW-LVL FLOW...SETUP MAY YIELD A FEW DISCRETE OR
SEMI-DISCRETE STORMS. THESE COULD POSE A LOW CONDITIONAL THREAT FOR
AN ISOLD TORNADO EARLY WED.
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z
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