SPC AC 220549
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1149 PM CST THU FEB 21 2008
VALID 231200Z - 241200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
IN MID/UPPER LEVELS...SPLIT FLOW PATTERN FCST TO CONTINUE ACROSS
WRN/CENTRAL CONUS...WITH NEARLY ZONAL SRN STREAM JET ACROSS SWRN
CONUS AND GULF STATES...AND RIDGING ALOFT SHIFTING EWD ACROSS NRN
PLAINS. SRN STREAM SHORTWAVE TROUGH IS APPARENT ATTM IN PROFILER
DATA AND MOISTURE CHANNEL IMAGERY OVER KS/WRN OK/NW TX. THIS TROUGH
IS EXPECTED TO DEAMPLIFY AS IT MOVES ENEWD ACROSS SRN APPALACHIANS
AND MID-ATLANTIC REGION...BECOMING ENTRAINED INTO BELT OF
CONFLUENT/CYCLONIC FLOW AROUND ERN CANADIAN UPPER TROUGH.
ASSOCIATED SFC COLD FRONT -- NOW ANALYZED OVER TX COASTAL PLAIN --
SHOULD MOVE OFFSHORE CAROLINAS AND GA COAST DAY-2...TRAILING SWWD
ACROSS NRN FL.
MEANWHILE...PERTURBATION NOW OFFSHORE NRN CA IS EXPECTED TO MOVE
ESEWD ACROSS GREAT BASIN DAY-1...REACHING CENTRAL/SRN HIGH PLAINS
AROUND 23/18Z...AND TN VALLEY REGION BY END OF PERIOD. SOME
FRONTOGENESIS AND ENHANCED SWD MOTION MAY OCCUR ALONG SEGMENT OF
AFOREMENTIONED FRONTAL ZONE LYING ACROSS NRN FL AND NEARBY
ATLANTIC...IN RESPONSE TO APCHG TROUGH.
...FL PENINSULA...
WIDELY SCATTERED TSTMS MAY DEVELOP PRIMARILY DURING AFTERNOON OVER
CENTRAL/NRN PORTIONS PENINSULA...AS SFC INSOLATION SUBSTANTIALLY
WEAKENS CINH. MOST FAVORABLE AREA FOR DEVELOPMENT WILL BE ALONG AND
S OF FRONT. SFC DEW POINTS MID-UPPER 60S F SHOULD BE
COMMON...COMBINING WITH DIABATIC HEATING TO OFFSET WEAK LOW-MIDDLE
LEVEL LAPSE RATES ABOVE BOUNDARY LAYER. THIS SHOULD SUPPORT MLCAPES
500-1000 J/KG. DEEP-LAYER SPEED SHEAR SHOULD BE SUFFICIENT TO BOOST
EFFECTIVE SHEAR MAGNITUDES TO AROUND 40 KT...SUPPORTING SOME
POSSIBILITY OF ORGANIZED CONVECTION. HOWEVER...COVERAGE AND
INTENSITY WILL BE LIMITED BY LACK OF LOW LEVEL CONVERGENCE...GIVEN
STG WLY SFC WIND COMPONENT NEAR AND S OF FRONT.
...S-CENTRAL PLAINS...AR...
ISOLATED TO WIDELY SCATTERED AND VERY ELEVATED TSTMS MAY DEVELOP
FROM LATE AFTERNOON OVER WRN PORTIONS THUNDER AREA...ESEWD ACROSS
OZARKS AND ADJACENT PORTIONS MS VALLEY THROUGH LATE EVENING AND
OVERNIGHT HOURS. STRONG DPVA AND ACCOMPANYING MID/UPPER LEVEL
ASCENT/DESTABILIZATION SHOULD IMMEDIATELY PRECEDE SHORTWAVE TROUGH
OVER THIS REGION. FCST SOUNDINGS SUGGEST UP TO 250 J/KG MUCAPE IS
POSSIBLE...ROOTED INVOF 700 MB. LIMITING FACTOR WILL BE MEAGER
MOISTURE...AND ACTIVITY IS NOT EXPECTED TO BE SVR.
..EDWARDS.. 02/22/2008
CLICK TO GET WUUS02 PTSDY2 PRODUCT
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z
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