SPC AC 081621
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1121 AM CDT WED SEP 08 2010
VALID 081630Z - 091200Z
...THERE IS A SLGT RISK OF SVR TSTMS TODAY ACROSS N CENTRAL TX AND S
CENTRAL OK...
...N CENTRAL TX/S CENTRAL OK TODAY...
THE REMNANTS OF TC HERMINE CONTINUE TO MOVE NWD/NNEWD FROM N TX TO
SRN OK. THE PRIMARY CONVECTIVE BAND IS LOCATED ALONG I-35 IN TX
/ALONG THE ERN EDGE OF THE MIDLEVEL DRY INTRUSION/...AND THIS BAND
SHOULD TRANSLATE SLOWLY NWD TODAY ACROSS N TX TO SRN OK. SOME
SURFACE HEATING IN CLOUD BREAKS AND A GRADUAL INCREASE TO MID 70S
DEWPOINTS WILL DRIVE AN INCREASE IN SURFACE-BASED INSTABILITY TOWARD
THE DFW AREA TODAY. MEANWHILE...THE BELT OF STRONGEST VERTICAL
SHEAR/SRH IS FOCUSED ALONG AND JUST E OF THE MAIN CONVECTIVE BAND
ACROSS N CENTRAL TX. THE LOW-LEVEL DESTABILIZATION WILL SUPPORT
ADDITIONAL CELLULAR STORM DEVELOPMENT IN THE ZONE OF FAVORABLE
LOW-LEVEL SHEAR PROFILES...THUS A FEW SUPERCELLS CAN BE
EXPECTED...WITH THE POTENTIAL FOR A COUPLE OF TORNADOES THIS
AFTERNOON. THE THREAT AREA WILL GRADUALLY SPREAD NWD TOWARD SRN OK
LATE TODAY INTO TONIGHT...THOUGH THE MAGNITUDE OF THE THREAT IS A
LITTLE MORE QUESTIONABLE IN OK GIVEN WEAKER INSTABILITY AND POOR
PHASING WITH THE DIURNAL CYCLE COMPARED TO N TX.
...ERN NEW ENGLAND TODAY...
A STRONG SHORTWAVE TROUGH AND ASSOCIATED COLD FRONT WILL SWEEP EWD
ACROSS THE REMAINDER OF NEW ENGLAND BY LATE AFTERNOON/EVENING. IN
THE INTERIM...A NARROW WARM SECTOR WILL PERSIST FROM ERN MA NNEWD TO
ERN MAINE. SURFACE HEATING AND LOW-LEVEL ASCENT ALONG THE COLD
FRONT COULD INITIATE ADDITIONAL STORMS EARLY THIS AFTERNOON ACROSS
ERN MAINE...WITH THE POTENTIAL FOR ISOLATED STRONG/DAMAGING WIND
GUSTS GIVEN STEEPENING LOW-LEVEL LAPSE RATES AND 50+ KT MIDLEVEL
FLOW.
...CENTRAL HIGH PLAINS LATER THIS AFTERNOON/EVENING...
A SERIES OF EMBEDDED SPEED MAXIMA ARE EJECTING NEWD FROM THE CENTRAL
ROCKIES TO THE HIGH PLAINS IN ADVANCE OF A DEEP PAC COAST TROUGH.
THE LEAD WAVE APPEARS TO BE THE STRONGEST AND IT IS ALREADY
OVERSPREADING NW NEB AND WRN SD. SOME INCREASE IN LOW-LEVEL
MOISTURE WILL CONTINUE ACROSS KS/NEB/SD IN RESPONSE TO HIGH PLAINS
LEE CYCLOGENESIS...BUT INSTABILITY SHOULD REMAIN MARGINAL THROUGH
THE AFTERNOON PER MODIFIED 12Z SOUNDINGS AND MODEL FORECAST
PROFILES. THUS...ANY DAMAGING WIND THREAT WITH CONVECTION SPREADING
NEWD FROM NE CO TOWARD SW NEB SHOULD LIKEWISE REMAIN MARGINAL.
OTHERWISE...EXPECT ELEVATED CONVECTION TO PERSIST TODAY ACROSS N/NE
NEB...WITH AN INCREASE IN COVERAGE NWD ACROSS ERN SD AND VICINITY
TONIGHT AS LOW-LEVEL MOISTURE INCREASES IN CONJUNCTION WITH THE LLJ.
SOME HAIL COULD OCCUR WITH THESE STORMS GIVEN MUCAPE OF 1000-1500
J/KG AND MIDLEVEL LAPSE RATES IN EXCESS OF 7 C/KM.
..THOMPSON/ROGERS.. 09/08/2010
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z
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