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 121930
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0230 PM CDT WED OCT 12 2011
   
   VALID 122000Z - 131200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS THERE IS A SLGT RISK OF SVR
   TSTMS THIS AFTERNOON AND EVENING OVER PARTS OF ERN KS...NERN
   OK...WRN MO...AND NWRN AR...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS THERE IS A SLGT RISK OF SVR
   TSTMS THIS AFTERNOON AND EVENING FROM PARTS OF ERN TX INTO WRN MS...
   
   ...20Z OUTLOOK UPDATE...
   SEVERE POTENTIAL STILL APPEARS GENERALLY LOW TO NEGLIGIBLE ACROSS
   MOST AREAS LATE THIS AFTERNOON AND EVENING.  IT IS DEBATABLE 
   WHETHER SLIGHT RISK PROBABILITIES ACROSS EASTERN PORTIONS OF THE
   CENTRAL/SOUTHERN PLAINS INTO THE LOWER MISSISSIPPI VALLEY ARE STILL
   JUSTIFIED DUE TO THE GENERALLY MARGINAL NATURE OF THE THREAT AND THE
   LIMITED ANTICIPATED COVERAGE OF POSSIBLE STORM REPORTS.  BUT THE
   1630Z IS BEING MAINTAINED...AS DISCUSSED BELOW.
   
   ..KERR.. 10/12/2011
   
   .PREV DISCUSSION... /ISSUED 1126 AM CDT WED OCT 12 2011/
   
   ...ARKLATEX/LOWER MS VALLEY NWD INTO THE OZARKS...
   
   HEIGHT FALLS WITHIN EXIT REGION OF STRONG MID- TO UPPER-LEVEL JET
   STREAK OVER THE CNTRL/SRN PLAINS WILL CONTRIBUTE TO AMPLIFICATION OF
   NEGATIVELY TILTED...FULL-LATITUDE TROUGH TRANSLATING INTO THE MS
   VALLEY.  AN ASSOCIATED COLD FRONT OVER THE GREAT PLAINS WILL
   ACCORDINGLY ADVANCE EWD INTO THE MS VALLEY BY TONIGHT.  
   
   COUPLING OF DCVA ATTENDANT TO MIDLEVEL TROUGH AND LOW-LEVEL UPLIFT
   ALONG SYNOPTIC COLD FRONT AND RESIDUAL OUTFLOW BOUNDARIES WILL
   FOSTER AN INCREASE IN STORM COVERAGE AND INTENSITY TODAY ACROSS THE
   REGION WITH ISOLATED OCCURRENCES OF HAIL AND LOCALLY STRONG WIND
   GUSTS POSSIBLE.  WITHIN THIS BROADER-SCALE REGIME...TWO REGIONS MAY
   HAVE A COMPARATIVELY HIGHER RISK FOR SEVERE STORMS.  THE FIRST AREA
   IS AHEAD OF THE COLD FRONT OVER ERN KS AND NERN OK INTO WRN MO AND
   NWRN AR.  HERE...RESIDUAL BOUNDARY LAYER DEWPOINTS IN THE UPPER
   50S-LOWER 60S WILL ALIGN WITH STRONGER DIABATIC HEATING ALONG WRN
   EDGE OF CLOUD SHIELD AND STEADILY COOLING MIDLEVEL TEMPERATURES TO
   YIELD MLCAPE VALUES APPROACHING 1000 J/KG.  WHILE DEEP-LAYER FLOW
   FIELD AND RESULTING VERTICAL SHEAR WILL REMAIN MARGINALLY SUPPORTIVE
   OF STORM ORGANIZATION...STEEPENING MIDLEVEL LAPSE RATES AND
   RELATIVELY COOL THERMODYNAMIC PROFILES WILL BE FAVORABLE FOR SEVERE
   HAIL PRODUCTION WITH THE MOST INTENSE STORMS THIS AFTERNOON AND
   EVENING.
   
   THE SECOND AREA OF GREATER SEVERE WEATHER POTENTIAL MAY DEVELOP FROM
   PORTIONS OF ERN TX EWD THROUGH NRN/CNTRL LA INTO WRN MS.  HERE...THE
   RE-DEVELOPMENT OF DIURNALLY ENHANCED STORMS IS ANTICIPATED ALONG
   LEADING EDGE OF RESIDUAL COLD POOL ASSOCIATED WITH NOCTURNAL STORM
   ACTIVITY.  WHILE MIDLEVEL LAPSE RATES WILL NOT BE AS STEEP AS POINTS
   TO THE N...THE BOUNDARY LAYER WILL BE MORE MOIST AND VERTICAL SHEAR
   WILL BE ENHANCED BY EXIT REGION OF MIDLEVEL JET STREAK DIGGING SEWD.
   AS SUCH...THE POTENTIAL WILL EXIST FOR SUPERCELL AND BOWING
   STRUCTURES CAPABLE OF MAINLY DAMAGING WIND GUSTS.  
   
   ...ERN NC INTO THE TIDEWATER...
   
   WATER VAPOR IMAGERY SHOWS A WEAKENING VORTICITY MAXIMUM LIFTING NEWD
   ACROSS THE REGION IN RESPONSE TO APPROACH OF UPSTREAM SYSTEM OVER
   THE GREAT PLAINS.  FORCING FOR ASCENT IN ADVANCE OF THIS FEATURE IS
   SUPPORTING AN INCREASE IN TSTMS OVER ERN NC WITHIN A MOIST AND
   WEAKLY CAPPED AIR MASS WITH MLCAPE VALUES OF 1000-2000 J/KG.  12Z
   OBSERVED SOUNDINGS AND CURRENT VAD DATA INDICATE THAT DEEP-LAYER
   WIND FIELD IS MARGINALLY SUPPORTIVE OF STORM ORGANIZATION/ROTATION
   WITH EFFECTIVE BULK SHEAR VALUES AROUND 30 KT.  HOWEVER...ELY
   LOW-LEVEL FLOW IN ADVANCE OF WEAK SURFACE LOW DEVELOPING NWD WILL
   MAINTAIN A CORRIDOR OF MODEST LOW-LEVEL SHEAR WHICH MAY PROMOTE SOME
   STORM ROTATION AND A LOW PROBABILITY RISK FOR DAMAGING WINDS AND
   PERHAPS A BRIEF TORNADO.
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z