SPC AC 240553

   DAY 2 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1153 PM CST WED DEC 23 2015

   VALID 251200Z - 261200Z

   ...THERE IS A MRGL RISK OF SVR TSTMS ACROSS PORTIONS OF THE LOWER OH
   VALLEY AND THE TN VALLEY TO THE LOWER MS VALLEY AND SRN GREAT
   PLAINS...

   ...SUMMARY...
   ISOLATED SEVERE THUNDERSTORMS WILL BE POSSIBLE ACROSS PORTIONS OF
   THE LOWER OHIO VALLEY AND TENNESSEE VALLEY TO THE LOWER MISSISSIPPI
   VALLEY AND SOUTHERN GREAT PLAINS FOR FRIDAY INTO FRIDAY NIGHT.

   ...SYNOPSIS...

   IN THE MID LEVELS...AMPLIFICATION OF A LARGE/DEEP TROUGH OVER THE
   WRN CONUS WILL OCCUR WHILE THE MEAN TROUGH POSITION SHIFTS EWD. A
   ZONE OF STRONG MID-LEVEL SWLYS WILL EXTEND NE OF THE TROUGH FROM
   PARTS OF THE SRN ROCKIES TO THE GREAT LAKES REGION. AS THIS
   OCCURS...SFC LOW PRESSURE WILL STRENGTHEN IN THE LEE OF THE
   CNTRL/SRN ROCKIES AND THEN DEVELOP ENEWD ALONG A STRONG COLD FRONT
   EMERGING OVER THE CNTRL/SRN HIGH PLAINS FROM THE W. AHEAD OF THE
   COLD FRONT...RICH GULF MOISTURE WILL BE TRANSPORTED NWD ACROSS
   PORTIONS OF THE SRN GREAT PLAINS...LOWER/MIDDLE MS VALLEY...AND
   OH/TN VALLEYS.

   ...PORTIONS OF THE LOWER OH VALLEY AND TN VALLEY TO THE LOWER MS
   VALLEY AND SRN GREAT PLAINS...

   AS THE LEADING EDGE OF RICHER MOISTURE MARKED BY A RESIDUAL FRONT
   ADVANCES NWD ACROSS PORTIONS OF THE GREAT PLAINS AND THE OH/TN/MS
   VALLEYS...TSTM POTENTIAL WILL ALSO EXTEND NWD THROUGH THE PERIOD.
   LARGE-SCALE DEEP ASCENT WILL BE LACKING. HOWEVER...WEAK LOW-LEVEL
   WARM ADVECTION COUPLED WITH DIURNALLY WEAKENED MLCINH AND BAROCLINIC
   CIRCULATIONS ATTENDANT TO THE RESIDUAL FRONT SHOULD SUPPORT ISOLATED
   TO SCATTERED TSTMS ACROSS AN UNSEASONABLY BROAD INLAND WARM
   SECTOR...WITH TSTM POTENTIAL CONTINUING INTO FRI NIGHT. THERE WILL
   BE A TENDENCY FOR TSTMS TO FOCUS ALONG THE NWD-ADVANCING BOUNDARY
   FROM PARTS OF THE RED RIVER VALLEY REGION TO THE LOWER OH VALLEY FRI
   NIGHT. EFFECTIVE BULK SHEAR ON THE ORDER OF 30-45 KT PERIPHERAL TO
   THE ZONE OF STRONG MID-LEVEL SWLYS MAY ENCOURAGE A FEW ROTATING
   UPDRAFTS AND SMALL QUASI-LINEAR SEGMENTS CAPABLE OF LOCALLY DMGG
   WIND GUSTS AND PERHAPS HAIL...GIVEN MLCAPE AROUND 500-1500 J/KG.
   LOW-LEVEL SHEAR WILL BE SUFFICIENTLY STRONG FOR SOME TORNADO RISK --
   PARTICULARLY IN PROXIMITY TO THE MOISTURE GRADIENT AND ESPECIALLY
   ACROSS PARTS OF N-CNTRL/NERN TX AND ERN OK/WRN AR FOR FRI NIGHT.
   HOWEVER...GIVEN THE DEARTH OF DEEP ASCENT...CONFIDENCE IN A
   GREATER-COVERAGE SVR RISK IS TOO LIMITED FOR HIGHER PROBABILITIES.

   ..COHEN.. 12/24/2015

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   NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z