SPC AC 290624

   DAY 2 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1224 AM CST WED JAN 29 2014

   VALID 301200Z - 311200Z

   ...NO SVR TSTM AREAS FORECAST...

   ...SYNOPSIS...
   AN AMPLIFIED FLOW PATTERN OVER THE CONUS WILL CONTINUE TO EVOLVE
   DURING DAY 2 INTO A ZONAL PATTERN...WITH A SPLIT IN THE UPPER FLOW
   REGIME DEVELOPING ACROSS THE WRN STATES.  SEVERAL SHORTWAVE TROUGHS
   WILL PROGRESS ACROSS THE CONUS ON THURSDAY INTO FRIDAY...WITH TWO
   PROVIDING SUPPORT FOR SOME CONVECTIVE THREAT AND/OR LIGHTNING
   POTENTIAL.  ONE IS A PACIFIC STORM SYSTEM EXPECTED TO MOVE ESEWD
   ACROSS CA APPROACHING THE GREAT BASIN...WHILE A SECOND TROUGH
   WEAKENS AS IT MOVES EWD ACROSS THE GULF OF MEXICO REACHING FL BY 12Z
   FRIDAY.

   ...S FL... 
   A SURFACE FRONT IS EXPECTED TO STALL S OF FL THROUGH MUCH OF
   THURSDAY WITH SURFACE DEWPOINTS INVOF COASTAL AREAS OF S AND SERN FL
   IN THE MID 60S AND PW VALUES EXCEEDING 1.5 INCHES.  GENERALLY WEAK
   UPPER FORCING THROUGH MUCH OF THE FORECAST PERIOD AND WEAK DEEP
   LAYER LAPSE RATES SHOULD TEND TO LIMIT TSTM POTENTIAL OVER S AND
   SERN FL THURSDAY AFTERNOON.  A GREATER POTENTIAL FOR TSTM
   DEVELOPMENT...THOUGH STILL RELATIVELY LOW /AROUND 10 PERCENT
   PROBABILITY/...COULD DEVELOP LATER THURSDAY NIGHT INTO EARLY FRIDAY
   MORNING.  INSTABILITY IS EXPECTED TO INCREASE LATE IN THE PERIOD AS
   TEMPERATURES IN THE 400-600 MB LAYER COOL...STEEPENING MIDLEVEL
   LAPSE RATES...WITH THE APPROACH OF THE GULF SHORTWAVE TROUGH. 
   EQUILIBRIUM TEMPERATURES SHOULD BECOME COLDER THAN -20 C SUPPORTING
   CHARGE SEPARATION/LIGHTNING POTENTIAL.

   ...HIGHER TERRAIN OF NRN/CENTRAL CA...
   AN INCREASE IN UPWARD VERTICAL ASCENT AND COOLING 500 MB
   TEMPERATURES/STEEPENING MIDLEVEL LAPSE RATES ARE EXPECTED AS THE
   PACIFIC SHORTWAVE TROUGH ADVANCES INLAND OVER CA AND THE WRN GREAT
   BASIN.  DESTABILIZATION ATTENDANT TO THESE PROCESSES SUGGESTS A
   POTENTIAL FOR A FEW LIGHTNING STRIKES...MAINLY OVER PARTS OF THE
   NRN/CENTRAL SIERRA MOUNTAINS.  FAIRLY WEAK INSTABILITY SHOULD LIMIT
   THE COVERAGE OF LIGHTNING SUCH THAT NO GENERAL TSTM AREA IS NEEDED
   WITH THIS OUTLOOK ISSUANCE.

   ..PETERS.. 01/29/2014

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