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 111637
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1137 AM CDT WED MAY 11 2011
   
   VALID 111630Z - 121200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM TEXAS ACROSS THE SRN
   PLAINS TO MIDWEST/WRN GREAT LAKES...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTIONS OF THE
   CAROLINAS...
   
   ...TX/OK...
   LEADING SHORT WAVE TROUGH EJECTING ENEWD OUT OF LARGER SCALE
   DEEP-LAYER CYCLONE ACROSS CO/NM WILL CONTINUE TO PROVIDE LARGE SCALE
   SUPPORT FOR PERSISTENCE OF DEEP CONVECTION FROM CNTRL TX NWD ACROSS
   OK THIS AFTERNOON. TIMING OF THIS FORCING WITH RESPECT TO DIURNAL
   HEATING CYCLE WILL MOST LIKELY LIMIT A MORE SUBSTANTIAL SEVERE
   WEATHER EPISODE FROM DEVELOPING ACROSS THESE AREAS AND ALSO
   INTRODUCES CONSIDERABLE UNCERTAINTY IN OVERALL SEVERE WEATHER
   SCENARIO.
   
   POCKETS OF GREATER DESTABILIZATION ALREADY OCCURRING AWAY AND
   DOWNSTREAM FROM ONGOING STORMS WILL SUPPORT A GRADUAL INCREASE IN
   CONVECTIVE VIGOR WITH DEEP-LAYER SHEAR PROFILES AND LARGE SCALE
   HEIGHT FALLS LEADING TO INCREASINGLY STRONGER AND MORE ORGANIZED
   STORMS. DAMAGING WINDS AND LARGE HAIL SHOULD BECOME MORE PREVALENT
   AS CONVECTION DEVELOPS/SPREADS NEWD ACROSS NCNTRL TX...SRN AND ERN
   OK THROUGH THIS AFTERNOON. THE THREAT FOR A COUPLE OF TORNADOES MAY
   ALSO INCREASE WITH TIME AS LOW LEVELS DESTABILIZE AND INHIBITION IS
   WEAKENED...AND SOME SEMBLANCE OF LOW LEVEL JET PERSISTS GENERALLY
   ACROSS THE RED RIVER AND INTO OK. OVERALL TORNADO ENVIRONMENT MAY
   REMAIN LIMITED BY LACK OF GREATER SURFACE DEVELOPMENT...ONGOING
   CONVECTION AND CONVECTIVE DEBRIS...AND VEERING LOW LEVEL FLOW WITH
   TIME. THERE IS ALSO SOME CHANCE THAT AIR MASS RECOVERY OCCURRING IN
   THE WAKE OF MORNING STORMS ACROSS SWRN OK COULD SUPPORT ISOLATED
   SUPERCELL DEVELOPMENT AHEAD OF THE DRYLINE IN THIS AREA. TORNADO
   POTENTIAL MAY INCREASE IF THIS DOES OCCUR.
   
   ...KS/NEB...
   AS IS THE CASE FARTHER SOUTH...SCENARIO IN THIS REGION IS
   COMPLICATED BY AN ARC OF ONGOING CONVECTION FROM NEB SWD ACROSS
   WRN/CNTRL KS. IT IS EXPECTED THAT THIS REGION WILL LIKELY EXPERIENCE
   GREATEST INFLUENCE/LIFT FROM THE EJECTING SHORT WAVE TROUGH.
   DESTABILIZATION UNDERWAY AHEAD OF CIRRUS CANOPY AND ALONG THE SHARP
   FRONTAL ZONE ALONG/NORTH OF KS/NEB BORDER WILL FUEL INCREASINGLY
   ROBUST TSTMS LATER TODAY AND INTO THIS EVENING. SHEAR PROFILES WILL
   BECOME FAVORABLE FOR UPDRAFT ROTATION AND PERSISTENCE AND MAGNITUDE
   OF LAPSE RATES WILL RESULT IN A GOOD CHANCE FOR LARGE HAIL. TORNADO
   THREAT WILL ALSO INCREASE FROM THE SLOW MOVING SURFACE LOW IN WRN KS
   ENEWD ALONG THE FRONT INTO SCNTRL NEB. WERE IT NOT FOR ONGOING
   CLOUDS AND CONVECTIVE DEBRIS...A GREATER TORNADO POTENTIAL WOULD
   LIKELY BE INDICATED IN THE OTLK. HOWEVER...GIVEN COMPLICATING
   FACTORS DUE TO CLOUDS/DESTABILIZATION IN ZONE OF STRONGEST
   ASCENT...THE STRONG TORNADO THREAT WILL NEED TO CONTINUALLY
   REASSESSED INTO THE AFTERNOON.
   
   WITH TIME EXPECT GREATER STORM CONVERGE AND INCREASING ORGANIZATION
   TO RESULT IN FORWARD PROPAGATING MCS THAT COULD PRODUCE DAMAGING
   WINDS EWD ACROSS PORTIONS OF SERN KS AND WRN MO LATER TODAY/THIS
   EVENING.
   
   ...WI/MI...
   INTENSE CONVECTION REMAINS ELEVATED AND NORTH OF SURFACE-BASED
   INSTABILITY AXIS FROM NRN WI ACROSS NRN LOWER MI. IT IS UNLIKELY
   THAT THIS ACTIVITY WILL ROOT INTO THE BOUNDARY LAYER BUT IT WILL
   CONTINUE TO POSE SOME CHANCE FOR HAIL. WEAK IMPULSES RIDING ALONG
   THE WRN FLANK OF THE UPPER RIDGE AXIS SHOULD LEAD TO A CHANCE FOR
   SURFACE-BASED DEVELOPMENT IN AN INCREASINGLY UNSTABLE REGIME FROM
   NERN IA ACROSS SRN WI AND PERHAPS EVEN NRN IL AND IND LATER TODAY.
   MODEST MID LEVEL WIND FIELDS WITH THE MID LEVEL DISTURBANCE MAY BE
   SUFFICIENT FOR FORWARD PROPAGATING MCS DEVELOPMENT GIVEN VERY MOIST
   AND UNSTABLE AIR MASS SITUATED ACROSS THE AREA. IN ADDITION TO LARGE
   HAIL...DAMAGING WINDS MAY ACCOMPANY THIS DEVELOPMENT.
   
   ...CAROLINAS...
   SOME INDICATION THAT WEAK PERTURBATIONS RIDING DOWN THE ERN FLANK OF
   THE UPPER RIDGE AXIS MAY CONTRIBUTE TO CONVECTIVE DEVELOPMENT ON THE
   ERN SLOPES OF THE APPALACHIANS LATER THIS AFTERNOON. THIS ACTIVITY
   MAY THEN SPREAD SWD INTO WARM AND UNSTABLE AIR MASS ACROSS THE
   CAROLINAS AND LEAD TO AN INCREASING CHANCE FOR DAMAGING WINDS AND
   PERHAPS HAIL NEARING 1 INCH IN DIAMETER.
   
   ..CARBIN/COHEN.. 05/11/2011
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z