SPC AC 231606
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1106 AM CDT SAT AUG 23 2008
VALID 231630Z - 241200Z
...THERE IS A SLGT RISK OF SVR TSTMS OVER MUCH OF NRN FL...AND PARTS
OF SRN GA AND SRN AL...
...SERN STATES...
CENTER OF T.S. FAY OVER CENTRAL FL PANHANDLE EXPECTED TO DRIFT WWD
TO NEAR MOB BY 12Z SUN. THERE WILL CONTINUE TO BE A THREAT OF BRIEF
TORNADOES ASSOCIATED WITH SMALL SCALE SUPERCELLS EMBEDDED IN THE
CONVECTIVE BANDS FROM OFF THE NERN GULF OF MEXICO. LOW LEVEL SHEAR
REMAINS MORE THAN ADEQUATE FOR STORM ROTATION...WITH THE PRIMARY
LIMITATION THE MARGINAL INSTABILITY.
REF MCD 2140 FOR MORE DETAILS CONCERNING THIS THREAT AREA.
...LWR MI INTO MID MS VALLEY...
COLD FRONT FROM ERN UP OF MI SW INTO IND/IL WILL SERVE AS
A FOCUS FOR LOW LVL ASCENT/SCTD STORM DEVELOPMENT THIS
AFTN. COMBINATION OF A FAIRLY MOIST BOUNDARY LAYER
/DEWPOINTS IN THE UPR 60S F TO NEAR 70 F/...MODEST MID LVL LAPSE
RATES...AND SFC HEATING SHOULD YIELD POCKETS OF 1500 TO PERHAPS 2000
J/KG SBCAPE. WITH THE STRONGEST DEEP ASCENT/FLOW REMAINING
POST-FRONTAL...PRIMARY STORM MODE SHOULD BE PULSE OR MULTICELL...
ESPECIALLY S OF LWR MI. A FEW OF THE STORMS COULD...HOWEVER...
PRODUCE LOCALLY DMGG WINDS AND POSSIBLY A FEW SPOTS OF HAIL THROUGH
EARLY EVENING.
...OK/KS...
CONVECTIVE GENERATED COLD POOL HAS PUSHED SWD INTO NRN OK THIS
MORNING. STRONG HEATING OF A RATHER MOIST BOUNDARY LAYER ACROSS OK
WILL GENERATE MLCAPES TO 1500-2000 J/KG THIS AFTERNOON. SCTD
THUNDERSTORMS MOST LIKELY VICINITY CONVERGENCE ON SURFACE BOUNDARY
WILL DEVELOP BY MID AFTERNOON. WHILE UPPER FLOW IS GENERALLY LESS
THAN 15KT...PULSE SEVERE IS POSSIBLE WITH PRIMARY THREAT DOWNBURST
WIND GUSTS.
THE COLD FRONT HAS STALLED ACROSS SRN KS AND TONIGHT A 20-30 KT LLJ
CENTRAL HIGH PLAINS WILL SUPPORT A FEW STRONG/SEVERE STORMS GIVEN
THE AVAILABLE MOIST/UNSTABLE AIRMASS RESIDING OVER THE PLAINS ALONG
AND S OF THE FRONT. GIVEN THE WEAK SHEAR AND RATHER WARM MID LEVEL
TEMPS UNDER THE UPPER RIDGE...ANY SEVERE THREAT WILL BE LIMITED TO
SOME MARGINAL HAIL EVENTS.
..HALES/CROSBIE.. 08/23/2008
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z
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