Categorical Graphic
Probabilistic Graphic
Probability of severe weather within 25 miles of a point. Hatched Area: 10% or greater probability of significant severe within 25 miles of a point.

   SPC AC 200730
   
   DAY 3 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0230 AM CDT FRI MAY 20 2011
   
   VALID 221200Z - 231200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS SUN FROM THE SOUTHERN PLAINS
   THROUGH THE MIDDLE MISSISSIPPI...OHIO AND TENNESSEE VALLEYS...
   
   ...SYNOPSIS...
   MODELS INDICATE THAT CIRCULATION AROUND LOW-LEVEL RIDGING DEVELOPING
   ALONG THE ATLANTIC SEABOARD WILL AID THE INLAND RETURN FLOW OF A
   MOIST GULF BOUNDARY LAYER DURING THE NEXT FEW DAYS.  LOWER/MID 70S
   SURFACE DEW POINTS ARE NOW PRESENT ACROSS MUCH OF THE GULF OF MEXICO
   INTO THE WESTERN GULF COAST REGION...AND...BY SUNDAY...DEW POINTS
   NEAR 70F MAY ADVECT THROUGH PORTIONS OF THE SOUTHERN PLAINS AND
   OZARK PLATEAU...INTO THE MIDDLE MISSISSIPPI AND LOWER OHIO VALLEYS. 
   THIS APPEARS LIKELY TO OCCUR COINCIDENT WITH THE NORTHEASTWARD
   ADVECTION OF ELEVATED MIXED LAYER AIR FROM THE SOUTHERN PLAINS AND
   PLATEAU REGION.  MODEST WEST SOUTHWESTERLY MID/UPPER FLOW IS
   EXPECTED TO PERSIST FROM THE SOUTHERN PLATEAU INTO THE NORTH
   ATLANTIC COAST STATES...JUST AHEAD OF LARGE-SCALE TROUGHING
   MIGRATING INLAND ACROSS THE PACIFIC COAST...AND SOUTH/ EAST OF A
   REMNANT CLOSED LOW ACCELERATING FROM THE NORTHERN PLAINS INTO THE
   UPPER MIDWEST...IN ADVANCE OF A SIGNIFICANT SHORT WAVE IMPULSE
   DIGGING ACROSS MANITOBA/ONTARIO.
   
   GUIDANCE IS SUGGESTIVE THAT MODERATE TO STRONG DESTABILIZATION WILL
   OCCUR OVER A RATHER BROAD AREA FROM THE SOUTHERN PLAINS INTO THE
   OHIO VALLEY...AND ADJACENT PORTIONS OF THE MISSISSIPPI AND TENNESSEE
   VALLEYS...BY EARLY SUNDAY AFTERNOON.  GIVEN ANTICIPATED WEAK TO
   MODEST INHIBITION AND FAVORABLE LARGE-SCALE FORCING FOR UPWARD
   VERTICAL MOTION...THIS IS EXPECTED TO ALLOW THE DEVELOPMENT OF
   CONSIDERABLE THUNDERSTORM ACTIVITY.  DEEP LAYER FLOW AND SHEAR
   ...WHILE NOT PARTICULARLY STRONG /PERHAPS ON THE ORDER OF 30-40
   KT/...IS EXPECTED TO BE SUFFICIENT FOR ORGANIZED CONVECTIVE
   DEVELOPMENT...INCLUDING ISOLATED SUPERCELLS...A COUPLE WHICH MAY BE
   CAPABLE OF PRODUCING TORNADOES...AND PERHAPS SEVERAL STORM CLUSTERS
   CAPABLE OF PRODUCING DAMAGING WINDS AND LARGE HAIL.  SEVERE STORMS
   COULD BECOME FAIRLY NUMEROUS BEFORE DIMINISHING WITH BOUNDARY LAYER
   STABILIZATION SUNDAY EVENING.
   
   ..KERR.. 05/20/2011
   
   CLICK TO GET WUUS03 PTSDY3 PRODUCT

   NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0730Z