SPC AC 011238

   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0738 AM CDT FRI NOV 01 2013

   VALID 011300Z - 021200Z

   ...THERE IS A SLGT RISK OF SVR TSTMS THIS MORNING OVER PARTS OF ERN
   PA AND NJ...

   ...SYNOPSIS...

   A SIGNIFICANT SHORT-WAVE TROUGH AND ASSOCIATED MID AND UPPER-LEVEL
   JET STREAKS OVER THE GREAT LAKES INTO CNTRL APPALACHIANS WILL EJECT
   NEWD INTO THE CANADIAN MARITIMES IN ADVANCE OF AN AMPLIFYING
   UPSTREAM TROUGH MOVING FROM THE GREAT PLAINS TO E OF THE MS RIVER
   VALLEY.

   THE PROGRESSION OF THE FORMER UPPER-AIR SYSTEM WILL RESULT IN THE
   EWD/NEWD ACCELERATION OF A SURFACE COLD FRONT TO OFF THE NERN U.S.
   COAST BY TONIGHT.  MEANWHILE...THE SRN PORTION OF THIS FRONT IS
   EXPECTED TO INTENSIFY E OF THE APPALACHIANS LATER TODAY AS
   LARGE-SCALE FORCING FOR ASCENT STRENGTHENS IN RESPONSE TO THE
   ARRIVAL OF THE LATTER SYSTEM MENTIONED ABOVE.  THERE IS SOME
   INDICATION IN LATEST MODEL GUIDANCE THAT ONE OR MORE WAVES MAY
   PROPAGATE NEWD ALONG THE COLD FRONT AS IT ADVANCES EWD TO OFF THE
   MIDDLE AND SERN ATLANTIC COASTS BY 02/12Z.

   ...MID ATLANTIC INTO NEW ENGLAND TODAY...

   A STRONGLY FORCED...LOW-TOPPED CONVECTIVE BAND WHICH PRODUCED FAIRLY
   WIDESPREAD WIND DAMAGE OVER THE OH VALLEY LAST NIGHT CONTINUES AS OF
   12Z FROM NERN MD TO SERN NY.  THIS FEATURE IS LARGELY BEING DRIVEN
   BY DCVA ASSOCIATED WITH THE GREAT LAKES SHORT-WAVE TROUGH AND
   LOW-LEVEL UPLIFT ALONG THE ATTENDING COLD FRONT.  WHILE AN INTENSE
   /70-80 KT/ SWLY LLJ WILL MAINTAIN THE FLUX OF AN INCREASINGLY MOIST
   AIR MASS AHEAD OF THIS CONVECTION...WEAK LAPSE RATES WILL LIMIT
   INSTABILITY WITH LITTLE OR NO LIGHTNING ANTICIPATED.  BUT GIVEN THE
   PRESENCE OF THE VERY STRONG WIND FIELD...LOCALLY DAMAGING WIND GUSTS
   WILL REMAIN POSSIBLE OWING TO DOWNWARD MOMENTUM TRANSFER WITHIN THE
   CONVECTIVE DOWNDRAFTS.

   FOR ADDITIONAL NEAR TERM GUIDANCE...SEE WW 559 AND MCD 2003.

   ...CNTRL/ERN CAROLINAS TO NERN GULF COAST THIS AFTERNOON INTO
   TONIGHT...

   AS MENTIONED IN THE SYNOPSIS...HEIGHT FALLS/FORCING FOR ASCENT
   ASSOCIATED WITHIN THE AMPLIFYING UPSTREAM TROUGH WILL SPREAD FROM
   THE MID/LOWER MS VALLEY INTO THE CNTRL/SRN APPALACHIANS DURING THE
   LATTER HALF OF THE FORECAST PERIOD. THIS WILL SUPPORT THE
   INTENSIFICATION OF THE SURFACE COLD FRONT AND NEWD PROPAGATION OF
   ONE OR MORE WAVES ALONG THE PIEDMONT AND COASTAL PLAIN.
   STRENGTHENING SLY/SWLY LOW-LEVEL FLOW AHEAD OF THE FRONT WILL
   MAINTAIN A SEASONABLY MOIST WARM SECTOR WITH BOUNDARY LAYER
   DEWPOINTS IN THE 60S TO PERHAPS LOWER 70S.  AND WHILE LAPSE RATES
   WILL REMAIN WEAK...THE HIGH MOISTURE CONTENT WILL YIELD POCKETS OF
   MODEST INSTABILITY WITH MLCAPE APPROACHING 500-1000 J/KG.

   THE GREATEST RISK FOR A FEW SEVERE STORMS IS EXPECTED TO DEVELOP
   LATE THIS AFTERNOON INTO EVENING FROM ERN GA NNEWD ACROSS THE ERN
   CAROLINAS...LIKELY IN ASSOCIATION WITH A WEAK SURFACE LOW DEVELOPING
   NEWD ALONG THE COLD FRONT.  HERE...FORECAST HODOGRAPHS SHOW A
   VERTICALLY VEERING WIND PROFILE WITH SUFFICIENT LOW-LEVEL AND
   DEEP-LAYER SHEAR FOR ORGANIZED STORM MODES...INCLUDING SUPERCELLS
   AND BOWING STRUCTURES.  DUE TO UNCERTAINTIES IN THE DEGREE OF AIR
   MASS DESTABILIZATION...SUB-SLIGHT RISK WIND AND TORNADO
   PROBABILITIES WILL BE MAINTAINED IN THIS FORECAST.

   ..MEAD/DEAN.. 11/01/2013

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   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z