Sep 5, 2012 0730 UTC Day 3 Severe Thunderstorm Outlook
Updated: Wed Sep 5 07:31:41 UTC 2012
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20120905 0730 UTC Day 3 Outlook Graphic
Probabilistic Graphic
20120905 0730 UTC Day Probabilitic 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 050729
   
   DAY 3 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0229 AM CDT WED SEP 05 2012
   
   VALID 071200Z - 081200Z
   
   ...SYNOPSIS...
   SUBSTANTIAL AMPLIFICATION OF THE UPPER PATTERN WILL OCCUR THIS
   PERIOD...AS A SHORT-WAVE TROUGH DIGS SEWD ACROSS THE CENTRAL CONUS
   AND EVOLVES INTO A FAIRLY LARGE/POSITIVELY TILTED SYSTEM BY THE END
   OF THE PERIOD.  AT THE SURFACE...A COLD FRONT ASSOCIATED WITH THE
   TROUGH WILL DIVE SWD ACROSS THE PLAINS...AS A FRONTAL LOW
   DEVELOPS/SHIFTS ENEWD ACROSS THE MID MS AND OH VALLEY THROUGH THE
   END OF THE PERIOD.  THIS SYSTEM WILL FOCUS A LARGE ZONE OF
   CONVECTION AND AT LEAST SOME SEVERE THREAT THROUGH THE PERIOD.
   
   ...OH VALLEY WSWWD INTO OK AND VICINITY...
   SHOWERS AND THUNDERSTORMS SHOULD BE ONGOING ACROSS PARTS OF THIS
   AREA AT THE START OF THE PERIOD -- PARTICULARLY ACROSS THE KS/MO
   VICINITY WHERE WARM ADVECTION ASSOCIATED WITH A SWLY LOW-LEVEL JET
   SHOULD BE MAXIMIZED.
   
   AS THE UPPER SYSTEM DIGS SEWD ACROSS THE PLAINS TOWARD THE MID
   MS/LOWER OH VALLEY REGION...A SURFACE COLD FRONT IS PROGGED TO SURGE
   QUICKLY SWD ACROSS THE CENTRAL PLAINS.  AS THIS OCCURS...A WEAK
   FRONTAL LOW IS FORECAST TO SHIFT ENEWD FROM THE OK VICINITY -- WITH
   WARM-SECTOR DESTABILIZATION SUPPORTING AN INCREASE IN CONVECTION
   ACROSS THE RISK AREA.  WHILE THE EVOLUTION REMAINS COMPLEX MAKING
   DETAILS DIFFICULT TO DISCERN ATTM...IT APPEARS THAT AS STRONGER FLOW
   ALOFT NUDGES EWD AND BEGINS TO SPREAD ATOP THE FRONTAL ZONE...SHEAR
   SUPPORTIVE OF ORGANIZED STORMS SHOULD EVOLVE.  WHILE THIS WILL BE
   PARTICULARLY TRUE AFTER DARK -- BEYOND THE PEAK CONVECTIVE
   CYCLE...OVERALL SETUP WARRANTS INCLUSION OF 5% PROBABILITY FOR
   HAIL/WIND ATTM.  AS DETAILS BECOME MORE CLEAR...UPGRADE TO SLIGHT
   RISK MAY BE NEEDED IN THE NEXT FORECAST PACKAGE.  
   
   CONVECTION WILL LIKELY CONTINUE OVERNIGHT AS A SWLY LOW-LEVEL JET
   RESULTS IN INCREASING WARM ADVECTION ACROSS THE MIDWEST/OH VALLEY
   AREA...BUT MUCH OF THE RESULTING CONVECTIVE ACTIVITY WILL REMAIN
   ELEVATED WITHIN ONLY A WEAKLY UNSTABLE AIRMASS -- THUS LIMITING
   OVERALL NIGHTTIME SEVERE THREAT.
   
   ..GOSS.. 09/05/2012
   
   CLICK TO GET WUUS03 PTSDY3 PRODUCT

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