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 190523
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1223 AM CDT SAT MAY 19 2012
   
   VALID 191200Z - 201200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTN AND EVE ACROSS THE
   CENTRAL PLAINS...
   
   ...SYNOPSIS...
   MODELS SUGGEST THAT BLOCKING MAY BECOME A BIT MORE PROMINENT WITHIN
   THE UPPER FLOW ACROSS THE EASTERN U.S. DURING THIS PERIOD ...AS AT
   LEAST A SHORT-LIVED EAST-WEST ELONGATED MID-LEVEL HIGH CENTER BUILDS
   ACROSS THE LOWER GREAT LAKES REGION AND NORTHEASTERN U.S...TO THE
   NORTH OF A LINGERING BROAD UPPER TROUGH/LOW ENCOMPASSING MUCH OF THE
   SOUTHEAST.  AS THIS OCCURS...AND MID-LEVEL HEIGHTS BEGIN TO RISE
   ACROSS THE WESTERN STATES...AHEAD OF A DEVELOPING TROUGH OVER THE
   EASTERN PACIFIC...THE SIGNIFICANT SHORT WAVE IMPULSE NOW CROSSING
   THE FOUR CORNERS REGION IS PROGGED TO LIFT NORTHEASTWARD ACROSS THE
   CENTRAL ROCKIES INTO THE NORTH CENTRAL PLAINS.
   
   DOWNSTREAM OF THIS LATTER FEATURE...MODERATELY STRONG SOUTHERLY
   LOW-LEVEL FLOW WILL PERSIST AHEAD OF A SURFACE COLD FRONT/LEE
   SURFACE TROUGH SLOWLY ADVANCING EASTWARD ACROSS THE PLAINS.  WHILE
   NORTHWARD MOISTURE ADVECTION WILL CONTRIBUTE TO FURTHER MOISTENING
   ACROSS THE PLAINS...SURFACE DEW POINTS ACROSS THE SOUTHERN PLAINS
   ARE STILL GENERALLY ONLY IN THE MID/UPPER 50S...AND SURFACE RIDGING
   EXTENDING SOUTHWESTWARD INTO THE WESTERN GULF COAST REGION WILL
   PRECLUDE AN INFLUX OF MORE SUBSTANTIVE MOISTURE OFF THE GULF OF
   MEXICO.  AS A RESULT...CONVECTIVE POTENTIAL IS EXPECTED TO REMAIN
   RELATIVELY LOW FOR MID TO LATE MAY...BUT DESTABILIZATION IS STILL
   EXPECTED TO BECOME SUFFICIENT TO SUPPORT AN INCREASING RISK FOR
   SEVERE STORMS TODAY ACROSS PARTS OF THE CENTRAL PLAINS INTO THE
   UPPER MISSISSIPPI VALLEY.  
   
   ...CENTRAL PLAINS INTO THE UPPER MISSISSIPPI VALLEY...
   THE SURFACE FRONTAL ZONE EXTENDING FROM THE UPPER MISSISSIPPI VALLEY
   INTO THE CENTRAL PLAINS IS EXPECTED TO PROVIDE A FOCUS FOR VIGOROUS
   STORM DEVELOPMENT TODAY.  HOWEVER...STRONGEST STORMS... WITH THE
   PRIMARY SEVERE WEATHER POTENTIAL...ARE EXPECTED TO FORM NEAR/EAST OF
   THE DRY LINE...FROM ITS INTERSECTION WITH THE FRONT ACROSS SOUTH
   CENTRAL NEBRASKA...SOUTHWARD INTO THE EASTERN TEXAS PANHANDLE
   REGION.  WARM ELEVATED MIXED LAYER AIR...WITH VERY STEEP MID-LEVEL
   LAPSE RATES...SHOULD SUPPRESS CONVECTIVE DEVELOPMENT UNTIL LATE
   AFTERNOON...AND ALLOW FOR A CORRIDOR OF STRONG BOUNDARY LAYER
   HEATING WHICH IS EXPECTED TO CONTRIBUTE TO MIXED LAYER CAPE ON THE
   ORDER OF 2000 J/KG.  AS AN AREA OF WEAK MID-LEVEL HEIGHT FALLS
   SHIFTS EAST OF THE ROCKIES THROUGH THE CENTRAL PLAINS BY THE 21-00Z
   TIME FRAME...ASSOCIATED LARGE-SCALE ASCENT SHOULD WEAKEN MID-LEVEL
   INHIBITION...AND ALLOW FOR THE INITIATION OF STORMS.
   
   IN ADDITION TO THE CONTINUING PRESENCE OF A MODERATELY STRONG
   PRE-FRONTAL SOUTHERLY LOW-LEVEL JET /30-40+ KT AT 850 MB/ ACROSS
   MUCH OF THE REGION...A 30-50 KT SOUTHWESTERLY 500 MB JET STREAK
   ACCOMPANYING THE UPPER IMPULSE SHOULD CONTRIBUTE TO A FAVORABLY
   STRONG AND SHEARED ENVIRONMENT FOR BOTH DISCRETE SUPERCELLS AND
   ORGANIZED STORM CLUSTERS.  A COUPLE OF TORNADOES APPEAR
   POSSIBLE...BUT SUB-CLOUD TEMPERATURE/DEW POINT SPREADS ARE EXPECTED
   TO BE FAIRLY SIZABLE...AND THIS THREAT MAY BE LIMITED TO THE MORE
   DISCRETE EARLY STORMS.  LARGE HAIL AND LOCALIZED DAMAGING DOWNBURSTS
   PROBABLY WILL BE THE MORE PROMINENT SEVERE  THREATS...THOUGH BROADER
   SCALE DAMAGING WIND POTENTIAL MAY ALSO NOT BE OUT OF THE QUESTION AS
   COLD POOLS CONSOLIDATE AND STRENGTHEN...BEFORE CONVECTION WEAKENS IN
   WANING INSTABILITY LATE THIS EVENING.
   
   ...FLORIDA PENINSULA...
   MODELS SUGGEST THAT STRONGEST LOW-LEVEL CONVERGENCE ASSOCIATED WITH
   SEA BREEZES WILL BECOME FOCUSED ACROSS INTERIOR...WEST CENTRAL AND
   SOUTHWESTERN PORTIONS OF THE PENINSULA TODAY.  AND RELATIVELY COOL
   MID-LEVEL AIR ASSOCIATE WITH THE LINGERING SOUTHEASTERN U.S. UPPER
   TROUGH/LOW MAY CONTINUE TO PROVIDE AT LEAST SOMEWHAT ENHANCED
   POTENTIAL FOR SEVERE HAIL AND LOCALIZED DOWNBURSTS.
   
   ..KERR/ROGERS.. 05/19/2012
   
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   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z