SPC AC 220533

   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1133 PM CST SAT DEC 21 2013

   VALID 221200Z - 231200Z

   ...NO SVR TSTM AREAS FORECAST...

   ...SYNOPSIS...
   SHORTWAVE IMPULSE NEAR THE LOWER MO VALLEY WILL DAMPEN AS IT RACES
   NEWD TOWARDS QUEBEC...WHILE UPSTREAM IMPULSES EFFECTIVELY MAINTAIN A
   LONGWAVE TROUGH ACROSS THE CNTRL CONUS. PRIMARY SURFACE CYCLONE
   ASSOCIATED WITH THE LEAD IMPULSE OVER THE MIDWEST WILL UNDERGO
   CYCLOLYSIS. NEVERTHELESS...ATTENDANT COLD FRONT SHOULD PUSH
   EWD...REACHING THE MID-ATLANTIC TO SOUTHEAST BY EARLY MON. 

   ...CNTRL GULF COAST/SOUTHEAST...
   AN EXTENSIVE CONVECTIVE BAND WILL BE ONGOING AT 12Z/SUN WITHIN A
   MARGINALLY BUOYANT BUT STILL STRONGLY SHEARED ENVIRONMENT. THIS
   CONVECTION COULD POSE A THREAT FOR STRONG TO ISOLATED DAMAGING WINDS
   AND PERHAPS A TORNADO EARLY IN THE DAY. HOWEVER...GIVEN LARGE-SCALE
   UPPER-LEVEL FORCING FOR ASCENT ALREADY FADING TO THE NORTH...VEERED
   LOW-LEVEL SWLYS FURTHER DIMINISHING AND DEEP-LAYER FLOW NEARLY
   PARALLELING THE BAND...CONVECTIVE INTENSITY SHOULD SUBSIDE INTO THE
   DIURNAL HEATING CYCLE. 

   ...LEE OF THE CNTRL APPALACHIANS...
   FARTHER N/NE...LOW-LEVEL SHEAR WILL REMAIN STRONG THROUGH THE DAY
   /ALBEIT DECREASING/. WITH MODEST SURFACE HEATING...PRESENCE OF LOWER
   TO MIDDLE 60S SURFACE DEW POINTS COULD YIELD MEAGER BUOYANCY WITH
   MLCAPE HOLDING AOB 500 J/KG. SOME DIURNAL INTENSIFICATION OF REMNANT
   OUTFLOW ASSOCIATED WITH THE NRN PORTION OF THE CONVECTIVE BAND MIGHT
   RESULT IN A RISK OF LOCALIZED DAMAGING WINDS.

   ..GRAMS/GOSS.. 12/22/2013

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   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z