Categorical Graphic
Probabilistic Tornado Graphic
Probability of a tornado within 25 miles of a point. Hatched Area: 10% or greater probability of EF2 - EF5 tornadoes within 25 miles of a point.
Probabilistic Damaging Wind Graphic
Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point. Hatched Area: 10% of greater probability of wind gusts 65 knots or greater within 25 miles of a point.
Probabilistic Large Hail Graphic
Probability of hail 1" or larger within 25 miles of a point. Hatched Area: 10% or greater probability of hail 2" or larger within 25 miles of a point.

   SPC AC 121251
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0751 AM CDT WED OCT 12 2011
   
   VALID 121300Z - 131200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM E TX AND THE ARKLATEX NNE
   INTO MO...
   
   ...SYNOPSIS...
   BROAD TROUGH NOW CENTERED OVER THE PLNS WILL CONTINUE TO AMPLIFY AS
   IT PROGRESSES SLOWLY E INTO THE MS AND LWR OH VLYS THIS PERIOD AND
   STRONG RIDGE PERSISTS OVER THE SOUTHWEST.  ELSEWHERE...REMNANTS OF
   EARLIER SERN U.S. TROUGH WILL CONTINUE TO LIFT NE ALONG THE
   APPALACHIANS/E CST.  
   
   AT THE SFC...WEAK COLD FRONT MARKING LEADING EDGE OF PLNS TROUGH
   WILL ADVANCE STEADILY E/SE FROM ERN PORTIONS OF THE CNTRL AND SRN
   PLNS INTO THE OZARKS AND LWR MS VLY.  THE NRN PART OF THE
   FRONT...MEANWHILE...WILL MOVE MORE SLOWLY E ACROSS THE UPR MS VLY. 
   IN THE EAST...WEAK BOUNDARY STALLED ALONG THE CAROLINA CST MAY EDGE
   A BIT INLAND OVER ERN NC/TIDEWATER VA LATER TODAY/TNGT AS WEAK LOW
   NOW OVER SC MOVES/REDEVELOPS SLOWLY NEWD.  
   
   ...ARKLATEX INTO OZARKS/MID MS VLY THIS AFTN/EVE...
   MID LVL LAPSE RATES WILL STEEPEN TODAY FROM ERN KS AND MO SSW
   THROUGH THE ARKLATEX AS DIFFLUENT/NEG TILT UPR TROUGH CONTINUES TO
   SLOWLY AMPLIFY.  MOISTURE RETURN AHEAD OF ASSOCIATED COLD FRONT WILL
   REMAIN MODEST /DEWPOINTS IN THE UPR 50S TO LOW 60S F WITH PW AROUND
   OR SLIGHTLY ABOVE 1 INCH/...AND CLOUDS WILL TEMPER SFC HEATING.  BUT
   GIVEN COOLING MID LVL TEMPS AND LOW LVL RETURN...DESTABILIZATION
   SHOULD BE SUFFICIENT /POCKETS OF SBCAPE OF 500 TO 1000 J PER KG/ TO
   SUPPORT DEVELOPMENT OF SCTD TSTMS AND/OR INTENSIFICATION OF EXISTING
   ACTIVITY FROM FAR ERN KS/MO SSW INTO ERN OK...NE TX...AR...AND NRN
   LA BY EARLY AFTN.  
   
   THE GREATEST SPEED AND DIRECTIONAL SHEAR SHOULD EXIST IN E TX...NEAR
   EXIT REGION OF UPR JET WHERE BELT OF ENHANCED 500 MB FLOW WILL BOOST
   NWLY DEEP SHEAR AOA 40 KTS.  SHEAR WILL REMAIN COMPARATIVELY WEAK IN
   MO...NEAR CORE OF TROUGH.  THAT REGION...HOWEVER...WILL EXPERIENCE
   STRONGER MID LVL COOLING... AND POSSIBLE GREATER SFC
   HEATING...RELATIVE TO POINTS SOUTH. 
   
   OVERALL SETUP SUGGESTS ONE IN WHICH SCTD STRONG TO SVR STORMS MAY
   OCCUR ON A SPORADIC BASIS THIS AFTN AND EVE JUST ABOUT ANYWHERE IN
   SLGT RISK AREA...WITH THE MAIN THREAT BEING HAIL.  OUTFLOW FROM
   LOOSELY ORGANIZED COMPLEX OF STORMS NOW IN N CNTRL/NE TX MAY SERVE
   TO FOCUS DEVELOPMENT IN THE ARKLATEX REGION AND MAY SUPPORT EVENTUAL
   DEVELOPMENT OF A SMALL BAND OF STORMS THAT MOVES SE TOWARD THE UPR
   TX GULF CST.  FARTHER NNE...POCKETS OF ENHANCED SFC HEATING BENEATH
   STRONGER MID LVL COOLING IN DEEP CYCLONIC FLOW SHOULD FOSTER
   MULTICELL CLUSTERS WITH HAIL AND PERHAPS LOCALLY DMGG WIND.
   
   ...UPR MS VLY...
   ALONG/AHEAD OF COLD FRONT...VERTICAL SHEAR AND BUOYANCY WILL BOTH
   REMAIN MARGINAL FOR SVR STORMS.  NEVERTHELESS...IN THE PRESENCE OF
   RELATIVELY STEEP LOW/MID LVL LAPSE RATES...A FEW STRONG OR
   MARGINALLY SVR PULSE STORMS WITH HAIL COULD OCCUR THIS AFTN/EARLY
   EVE.
   
   ...CAROLINAS/SE VA TODAY/TNGT...
   RELATIVELY MOIST...LOW AMPLITUDE...CYCLONIC SW MID/UPR LVL FLOW WILL
   PREVAIL OVER THE CAROLINAS AND MID ATLANTIC AS OLD TROUGH COMPLEX
   CONTINUES TO WEAKEN AND LIFT NE ACROSS REGION. LOW LVL SHEAR SHOULD
   REMAIN WEAK IN MOST AREAS...BUT MAXIMIZED INVOF WEAK FRONT MENTIONED
   IN THE SYNOPSIS.  SUFFICIENT LOW LVL FLOW WILL EXIST OVER CSTL NC/VA
   SUCH THAT A SUPERCELL/BRIEF TORNADO THREAT CANNOT BE RULED OUT AS
   WEAK SFC LOW TRACKS ACROSS REGION.  OTHERWISE...DAYTIME
   HEATING/DESTABILIZATION MAY BE SUFFICIENT TO YIELD A FEW STRONGER
   STORMS WITH LOCALLY DMGG WIND OVER ERN AND CNTRL PARTS OF THE
   CAROLINAS THIS AFTN.
   
   ..CORFIDI/LEITMAN.. 10/12/2011
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z