SPC AC 101622
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1122 AM CDT SAT OCT 10 2009
VALID 101630Z - 111200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
FAST CYCLONIC FLOW REGIME DOMINATES MUCH OF THE CONUS UPPER AIR
PATTERN TODAY AS THE REMNANTS OF A SRN/MIDDLE STREAM SHORT WAVE
TROUGH IN THE EAST CONTINUE TO PHASE WITH EXTENSIVE NRN STREAM
TROUGHING ACROSS NRN U.S. AND CANADA. FRONTAL ZONE ASSOCIATED WITH
THE LEAD DEAMPLIFYING TROUGH HAS CROSSED THE APPALACHIANS AND WAS
SITUATED FROM NERN NC SWWD TO FL PNHDL. WHILE THE FRONT IS FORECAST
TO PROGRESS EWD/SEWD ACROSS THE REST OF THE SOUTHEAST ATLANTIC
COASTAL PLAIN FROM NC TO GA THROUGH TODAY/TONIGHT...THE TRAILING
PORTION OF THIS BOUNDARY WILL LIKELY STALL FROM GA/FL BORDER WWD
INTO THE NRN GULF OF MEXICO. TSTMS WILL BE MOST LIKELY FROM PARTS OF
FL...NWD ALONG AND AHEAD OF THE ADVANCING FRONT IN AN INCREASINGLY
NARROW CORRIDOR FROM SERN GA TO ERN NC.
...SOUTHEAST COAST...
VERY MOIST AND UNSTABLE PRE-FRONTAL AIRMASS SHOULD CONTRIBUTE TO AN
INCREASE IN TSTM ACTIVITY FROM ERN NC TO ERN GA THROUGH THE
AFTERNOON. GUSTY WINDS AND HEAVY RAIN ARE LIKELY TO ACCOMPANY THESE
STORMS. HOWEVER...WLY LOW LEVEL FLOW ACROSS THE WARM SECTOR IS
LIKELY TO REDUCE NEAR SURFACE CONVERGENCE AS STRONGER MASS INFLOW
AND SUPPORT FOR ENHANCED LARGE SCALE ASCENT BECOME INCREASINGLY
DISPLACED TO THE NORTH AND OFFSHORE. ADDITIONALLY...GENERALLY WEAK
MID LEVEL LAPSE RATES WILL INHIBIT STRONGER UPDRAFT INTENSITY FROM
DEVELOPING DESPITE VERY MOIST BOUNDARY LAYER CONDITIONS.
OFFSETTING THESE LIMITATIONS...DEEP-LAYER WLY FLOW OF 40-50KT ABOVE
THE BOUNDARY LAYER WILL RESULT IN SUFFICIENT SHEAR FOR STORM
PERSISTENCE/ORGANIZATION. AND...WEAK SURFACE WAVE NEAR FRONTAL
SEGMENT INTERSECTION...FROM SC INTO SERN NC...COULD LOCALLY SUPPORT
A SMALL MCS DEVELOPING AS INDICATED BY 00Z 4KM WRF-NMM AND WRF-ARW
MODEL RUNS. BOTH AREAL COVERAGE AND DURATION OF SEVERE WIND
POTENTIAL WITH THIS ACTIVITY DOES NOT APPEAR TO WARRANT AN INCREASE
IN OVERALL SEVERE WEATHER PROBABILITIES AT THIS TIME.
...FL...
STORMS WILL ALSO BE ON THE INCREASE ACROSS PARTS OF NRN/NERN FL THIS
AFTERNOON. MOIST AND MODERATELY UNSTABLE CONDITIONS AMIDST WEAK
SEABREEZE BOUNDARY INTERACTIONS COULD SUPPORT A FEW MORE INTENSE
CORES. SHEAR AND ASCENT ACROSS THE REGION ARE WEAKER THAN POINTS
NORTH BUT AN ISOLATED DOWNBURST WIND EVENT CANNOT BE RULED OUT GIVEN
ANTICIPATED STORM COVERAGE.
..CARBIN/GRAMS.. 10/10/2009
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z
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