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 120049
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0749 PM CDT WED MAY 11 2011
   
   VALID 120100Z - 121200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS THIS EVENING FROM PARTS OF THE
   CENTRAL PLAINS/MID MISSOURI AND MISSISSIPPI VALLEYS INTO THE GREAT
   LAKES REGION...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS TONIGHT ACROSS PARTS OF SOUTH
   CENTRAL TEXAS...
   
   ...CENTRAL PLAINS INTO GREAT LAKES REGION...
   A MID-LEVEL CLOSED LOW HAS LIFTED OUT OF THE FOUR CORNERS REGION
   INTO THE CENTRAL HIGH PLAINS...BUT EMBEDDED WITHIN THE PREVAILING
   LARGER SCALE BLOCKING PATTERN...LITTLE ADDITIONAL MOVEMENT IS
   EXPECTED THROUGH THE REMAINDER OF THE FORECAST PERIOD.  ONE SHORT
   WAVE PERTURBATION PIVOTING AROUND ITS EASTERN AND NORTHERN PERIPHERY
   MAY ENHANCE LARGE SCALE ASCENT ALONG AN AXIS FROM SOUTHWEST NEBRASKA
   THROUGH NORTHERN IOWA BY LATE EVENING...WHERE CONVECTIVE DEVELOPMENT
   MAY BECOME FOCUSED AND LINGER THROUGH EARLY THURSDAY. 
   HOWEVER...THIS APPEARS LIKELY TO BE BASED ABOVE RESIDUAL OUTFLOW
   BOUNDARIES ACROSS PARTS OF THE MIDDLE MISSOURI AND MIDDLE
   MISSISSIPPI VALLEYS...AND A QUASI-STATIONARY SURFACE FRONTAL ZONE
   ACROSS THE NORTH CENTRAL PLAINS...WITH INCREASINGLY LIMITED SEVERE
   POTENTIAL.
   
   ONGOING THUNDERSTORM ACTIVITY...IN GENERAL...APPEARS WELL PAST PEAK
   INTENSITY...BUT LINGERING INSTABILITY...ALONG AFOREMENTIONED SURFACE
   BOUNDARIES AND ANOTHER GUST FRONT NOW ADVANCING NORTHEASTWARD TOWARD
   THE MISSOURI OZARKS...REMAINS SUFFICIENTLY STRONG TO MAINTAIN SLIGHT
   RISK PROBABILITIES THROUGH AT LEAST THE 03-06Z TIME FRAME.  
   
   IT MAY NOT BE OUT OF THE QUESTION THAT FORCING ASSOCIATED WITH A
   WEAK IMPULSE TOPPING THE CREST OF AN UPPER RIDGE OVER THE SOUTHERN
   GREAT LAKES REGION COULD STILL SUPPORT UPSCALE CONVECTIVE GROWTH
   LATE THIS EVENING.  MIXED LAYER CAPE REMAINS FAIRLY STRONG ON THE
   ORDER OF 2000-3000 J/KG ACROSS THIS REGION... BUT WEAK DEEP LAYER
   FLOW FIELDS AND SHEAR MAY ULTIMATELY LIMIT THE OVERALL CONVECTIVE
   POTENTIAL.
   
   ...SOUTH CENTRAL TEXAS...
   INSTABILITY ASSOCIATED WITH STEEP LAPSE RATES AND LARGE CAPE...
   COUPLED WITH MODEST VERTICAL SHEAR...ARE MAINTAINING STRONG/SEVERE
   STORM DEVELOPMENT ON THE SOUTHERN FLANK OF THE LARGE WEAKENING
   SOUTHERN PLAINS STORM CLUSTER.  THIS ACTIVITY MAY BEGIN TO WEAKEN BY
   LATE EVENING WITH THE LOSS OF BOUNDARY LAYER HEATING. 
   HOWEVER...VARIOUS MODEL DATA HAVE SUGGESTED THAT FORCING ASSOCIATED
   WITH AN IMPULSE WITHIN THE SUBTROPICAL JET COULD SUPPORT RENEWED
   STRONG/SEVERE STORM DEVELOPMENT TOWARD 09-12Z...OFF THE HIGHER
   TERRAIN OF MEXICO...AND NEAR THE DRY LINE/OUTFLOW BOUNDARY
   INTERSECTION...NEAR OR SOUTH OF DEL RIO.
   
   ..KERR.. 05/12/2011
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z