SPC AC 190730

   DAY 3 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0230 AM CDT WED JUN 19 2013

   VALID 211200Z - 221200Z

   ...THERE IS A SLGT RISK OF SVR TSTMS FOR PARTS OF THE NRN/CNTRL
   PLAINS TO THE UPPER MS VALLEY...

   ...SYNOPSIS...
   AN UPPER-LEVEL TROUGH SHOULD DAMPEN SLIGHTLY AS IT REMAINS ANCHORED
   OVER THE NRN INTERMOUNTAIN WEST INTO EARLY SAT...WITH EMBEDDED
   IMPULSES ROTATING THROUGHOUT IT. A DOWNSTREAM MID-LEVEL ANTICYCLONE
   SHOULD HOLD OVER THE SRN PLAINS WITH A RIDGE EMANATING NWD INTO THE
   UPPER MIDWEST. A BELT OF MODERATE MID-LEVEL W/SWLYS WILL PERSIST
   ACROSS THE N-CNTRL CONUS...WHICH MAY BE ENHANCED BY
   CONVECTIVELY-INDUCED IMPULSES. AT THE SURFACE...A LEE THERMAL LOW
   SHOULD BE CENTERED OVER NERN CO FRI AFTERNOON...WITH A
   SW/NE-ORIENTED WEAK SURFACE FRONT EXTENDING INTO THE UPPER MIDWEST.
   THIS FRONT AND PERHAPS ADDITIONAL OUTFLOW BOUNDARIES WILL LIKELY BE
   MODULATED BY A PROBABLE MCS ON D2. 

   ...NRN/CNTRL PLAINS TO THE UPPER MS VALLEY...
   TSTM CLUSTERS MAY BE ONGOING OVER PARTS OF THE UPPER MS VALLEY
   WITHIN A LOW-LEVEL WAA REGIME. THIS ACTIVITY MAY DIURNALLY
   STRENGTHEN AND POSE A RISK FOR ISOLATED SEVERE WIND/HAIL AS IT
   SPREADS E/SEWD ALONG THE LEADING EDGE OF THE EML. 

   FARTHER W...A RESERVOIR OF STRONG TO EXTREME INSTABILITY APPEARS
   LIKELY TO DEVELOP FRI AFTERNOON ALONG AND S OF THE AFOREMENTIONED
   SURFACE FRONT WITHIN A PLUME OF VERY STEEP MID-LEVEL LAPSE RATES AND
   ENRICHING LOW-LEVEL MOISTURE BENEATH A CAPPING INVERSION. LOW-LEVEL
   UPSLOPE FLOW TO THE N OF THE BOUNDARY AND PERHAPS GLANCING INFLUENCE
   OF A SHORTWAVE IMPULSE ROTATING ACROSS THE NRN HIGH PLAINS SHOULD
   AID IN AFTERNOON TSTM DEVELOPMENT NEAR THE HIGHER TERRAIN INVOF
   BLACK HILLS. WITH STRONG EFFECTIVE SHEAR...ACTIVITY SHOULD MATURE
   INTO SUPERCELLS CAPABLE OF PRODUCING VERY LARGE HAIL AND A FEW
   TORNADOES. AS THE LLJ STRENGTHENS OVER THE CNTRL PLAINS/MID-MO
   VALLEY FRI EVENING...CONSOLIDATING COLD POOLS SHOULD YIELD UPSCALE
   GROWTH INTO AN MCS. GIVEN THE DEGREE OF INSTABILITY ON THE FRINGE OF
   SUFFICIENT DEEP-LAYER SHEAR...POTENTIAL EXISTS FOR BOWS CAPABLE OF
   SIGNIFICANT SEVERE WIND.

   ..GRAMS.. 06/19/2013

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