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 140730
   
   DAY 3 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0230 AM CDT TUE AUG 14 2012
   
   VALID 161200Z - 171200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE MIDWEST/MIDDLE MS
   RIVER VALLEY/OZARKS...
   
   ...SYNOPSIS...
   AN AMPLIFIED LONGWAVE FLOW REGIME WILL PERSIST OVER THE CONUS INTO
   THURSDAY. THE PATTERN WILL BE HIGHLIGHTED BY A DEEP/EXTENSIVE
   LONGWAVE TROUGH CENTERED OVER EAST-CENTRAL CANADA AND THE GREAT
   LAKES REGION...TO THE NORTH AND EAST OF A BROAD UPPER RIDGE OVER THE
   WESTERN/SOUTHERN CONUS.
   
   ...MIDWEST/GREAT LAKES REGION AND MIDDLE MS VALLEY/OZARKS...
   THE SOUTHERN PART OF THE AFOREMENTIONED LONGWAVE TROUGH IS EXPECTED
   TO CONTINUE TO AMPLIFY/DEVELOP EASTWARD OVER THE GREAT LAKES REGION
   AND MIDWEST ON THURSDAY. AN ASSOCIATED COLD FRONT...POTENTIALLY
   AUGMENTED BY EARLY DAY PRECIPITATION/CLOUD COVER ACROSS THE UPPER MS
   VALLEY AND WESTERN GREAT LAKES VICINITY...WILL MAKE A STEADY
   EASTWARD PROGRESSION ACROSS MUCH OF THE REGION...WITH A SLOWER/MORE
   SOUTHEASTWARD MOVEMENT OF THE FRONT ACROSS THE OZARKS AND SOUTHERN
   PLAINS.
   
   IT SEEMS LIKELY THAT TSTMS WILL INCREASE/INTENSIFY THURSDAY
   AFTERNOON ALONG OR /MORE SO/ AHEAD OF THE /EFFECTIVE/ COLD FRONT
   WITHIN A RELATIVELY MOIST/MODERATELY UNSTABLE BOUNDARY LAYER.
   CURRENT INDICATIONS ARE THAT THE RELATIVELY STRONGEST
   DESTABILIZATION WILL OCCUR THURSDAY AFTERNOON ACROSS THE OZARKS INTO
   DOWNSTATE IL AND PERHAPS INDIANA...WITH AS MUCH AS 1500-2500 J/KG
   MLCAPE POSSIBLE. THE STRONGEST FORCING FOR ASCENT/VERTICAL SHEAR
   WILL TEND TO LAG THE COLD FRONT EXCEPT FOR THE GREAT LAKES REGION
   WHERE THE EXTENT OF DIURNAL DESTABILIZATION IS MORE QUESTIONABLE
   OWING TO EARLY DAY CLOUD COVER/PRECIPITATION UNCERTAINTIES AND LOWER
   OVERALL THETA-E. EVEN REMOVED FROM THE STRONGER FORCING/VERTICAL
   SHEAR...STRONGER/MORE CERTAIN DESTABILIZATION FARTHER SOUTHWEST INTO
   THE MIDDLE MS VALLEY/OZARKS WILL ACCOUNT FOR ORGANIZED/SUSTAINED
   SEVERE TSTM POTENTIAL THURSDAY AFTERNOON INTO MID-EVENING. DAMAGING
   WINDS AND BOUTS OF SEVERE HAIL WILL BE THE PRIMARY HAZARDS. TSTMS
   SHOULD CONTINUE TO SPREAD EAST-SOUTHEASTWARD THURSDAY NIGHT ACROSS
   THE OH VALLEY/LOWER GREAT LAKES/MID-SOUTH...BUT WITH A DIMINISHING
   SEVERE THREAT BY THE LATE EVENING/OVERNIGHT HOURS.
   
   ...SOUTHERN PLAINS/MID-SOUTH...
   ALTHOUGH WELL-REMOVED FROM THE STRONGER WESTERLIES ALOFT OVER THE
   MIDWEST...ISOLATED TO SCATTERED TSTMS ARE EXPECTED TO DEVELOP
   ALONG/AHEAD OF THE SOUTHEASTWARD MOVING COLD FRONT ACROSS THE
   REGION. A HOT/DEEPLY MIXED BOUNDARY LAYER WILL ACCOUNT FOR ISOLATED
   DOWNBURST POTENTIAL THURSDAY AFTERNOON/EARLY EVENING.
   
   ...SOUTHERN AZ...
   MOISTURE SEEMS LIKELY TO STEADILY INCREASE INTO SOUTHERN AZ/LOWER CO
   RIVER VALLEY BY THURSDAY...WITH A RESULTANT UPSWING IN TSTMS
   PROBABLE ACROSS THE REGION. ESPECIALLY IF IT COINCIDES WITH A
   MODESTLY INCREASING EASTERLY STEERING COMPONENT ON THE IMMEDIATE
   PERIPHERY OF THE UPPER RIDGE...TSTMS MAY REACH THE SOUTHERN AZ
   DESERT FLOOR WITH DOWNBURSTS AND STRONG/GUSTY WINDS POSSIBLE.
   
   ..GUYER.. 08/14/2012
   
   CLICK TO GET WUUS03 PTSDY3 PRODUCT

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