SPC AC 101928
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0128 PM CST TUE NOV 10 2009
VALID 102000Z - 111200Z
...NO SVR TSTM AREAS FORECAST...
...20Z UPDATE...
BOUNDARY LAYER DESTABILIZATION...OR THE LACK THEREOF...REMAINS THE
MOST PROMINENT ISSUE CONCERNING CONVECTIVE/SEVERE POTENTIAL THROUGH
THE BALANCE OF THIS FORECAST PERIOD. A TONGUE OF LOWER 70S SURFACE
DEW POINTS DOES APPEAR TO BE ADVECTING INLAND ACROSS THE FLORIDA BIG
BEND REGION INTO SOUTHEASTERN ALABAMA...AHEAD OF THE WEAKENING
SURFACE LOW CENTER OVER THE WESTERN FLORIDA PANHANDLE. BUT...A WARM
MID-LEVEL AIR MASS ACCOMPANYING IDA CONTINUES TO SUPPRESS CONVECTIVE
DEVELOPMENT. TO THIS POINT... THUNDERSTORM ACTIVITY IS BEEN
CONFINED TO THE EASTERN GULF OF MEXICO.
HOWEVER...GUIDANCE REMAINS SUGGESTIVE THAT WEAK DIFFERENTIAL THERMAL
ADVECTION COULD CONTRIBUTE TO SUFFICIENT DESTABILIZATION FOR
ISOLATED TO WIDELY SCATTERED THUNDERSTORM ACTIVITY AHEAD OF AN UPPER
TROUGH AXIS SHIFTING EASTWARD INTO THE EASTERN GULF STATES LATER
THIS EVENING. THIS COULD BE BOUNDARY LAYER BASED ACROSS THE FLORIDA
BIG BEND/NORTH CENTRAL FLORIDA...WHERE SOUTHERLY 850 MB FLOW MAY
REMAIN ON THE ORDER OF 30-40 KT...CONTRIBUTING TO SIZABLE CLOCKWISE
CURVED LOW-LEVEL HODOGRAPHS SUPPORTIVE OF AT LEAST NON- NEGLIGIBLE
TORNADO PROBABILITIES.
..KERR.. 11/10/2009
.PREV DISCUSSION... /ISSUED 1019 AM CST TUE NOV 10 2009/
...SYNOPSIS...
LOW AMPLITUDE/PROGRESSIVE FLOW REGIME WILL BE MAINTAINED ACROSS MUCH
OF THE LOWER 48 ASIDE FROM A MID-LEVEL TROUGH INTERACTING WITH
DECAYING T.D. IDA OVER PORTIONS OF THE SERN U.S. AT THE
SURFACE...AN ELONGATED SURFACE FRONT EXTENDS FROM NEW ENGLAND SWWD
TO THE SRN PLAINS. THIS FEATURE WILL CONTINUE TO SLIDE SEWD OVER
PARTS OF THE MID-ATLANTIC AND OH VALLEY. IDA/S CENTER THIS MORNING
WAS ANALYZED NEAR THE FL/AL GULF COAST...AND IT WILL SLOWLY MEANDER
EWD OVER PARTS OF THE FL PANHANDLE THROUGH THE PERIOD ACCORDING TO
LATEST NHC FORECAST.
...NERN GULF COAST...
MORNING VISIBLE SATELLITE/RADAR MOSAIC DATA SHOW A BAND OF
CONVECTION ALIGNED FROM EXTREME SW GA/E FL PANHANDLE SWD INTO THE
E-CNTRL GULF. AS T.D. IDA WEAKENS AND BECOMES MORE HYBRID-LIKE AND
EXTRATROPICAL WITH TIME...LOW LEVEL FLOW FIELDS ARE EXPECTED TO
WEAKEN CONSIDERABLY BY WEDNESDAY MORNING AS THE LOW LEVEL JET BEGINS
TO SLIGHTLY VEER AND SHIFT NWD TO THE GA/CAROLINA PIEDMONT PARTLY IN
RESPONSE TO UPPER TROUGH FROM THE W SHIFTING N AND EWD OVER THE SERN
U.S. WITH THAT SAID...VERY MOIST LOW LEVEL AIR MASS WITHIN MORE
THAN ADEQUATELY SHEARED ENVIRONMENT WILL CONDITIONALLY REMAIN
SUPPORTIVE FOR PERHAPS AN ISOLD DMGG WIND GUST OR TORNADO...MAINLY
WITH ANY ROBUST UPDRAFT LOCATED ALONG THE LOW LEVEL CONFLUENCE ZONE
SPREADING EWD ACROSS THE ERN FL PANHANDLE AND EVENTUALLY INTO THE
BIG BEND/WRN PORTIONS OF THE FL PENINSULA THIS AFTERNOON/EVENING.
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z
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