SPC AC 191301

   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0701 AM CST FRI DEC 19 2014

   VALID 191300Z - 201200Z

   ...NO SVR TSTM AREAS FORECAST...

   ...SUMMARY...
   WIDELY SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY OVER PARTS OF
   CENTRAL AND SOUTH TEXAS...ACROSS SOUTHERN LOUISIANA TO
   MOBILE/PENSACOLA AREAS.

   ...SYNOPSIS...
   UPPER-AIR PATTERN IS FCST TO REMAIN FAIRLY LOW-AMPLITUDE
   SYNOPTICALLY...AND PROGRESSIVE IN NATURE...AS NUMEROUS MAINLY
   LOW-AMPLITUDE PERTURBATIONS TRAVERSE CONUS.  SHORTWAVE TROUGH NOW
   LOCATED OVER W TX IS EXPECTED TO DEAMPLIFY GRADUALLY AS IT MOVES
   ENEWD TO ARKLATEX REGION BY 00Z...AND SRN APPALACHIANS BY END OF
   PERIOD. 

   AT SFC...LOOSELY ASSOCIATED FRONTAL-WAVE LOW WAS ANALYZED AT 11Z
   OVER MIDDLE TX COASTAL PLAIN JUST INLAND FROM CRP...WITH
   WAVY/QUASISTATIONARY FRONT ENEWD OVER MIDDLE-UPPER TX COASTAL WATERS
   AND OFFSHORE LA.  COLD FRONT EXTENDED FROM LOW SWD ACROSS LOWER TX
   COASTAL COUNTIES AND OVER COASTAL PLAIN OF EXTREME NERN MEX.  WITH
   PRIMARY SHORTWAVE TROUGH PASSING N OF THIS REGION WHILE
   WEAKENING...SFC LOW IS FCST TO REMAIN WEAK AND MOVE SLOWLY EWD THEN
   ENEWD OVER NWRN GULF ALONG FRONTAL ZONE.  LOW SHOULD REMAIN MOSTLY
   OVER WATER...THOUGH IT MAY REACH MS RIVER MOUTH AROUND 20/12Z. 
   FRONT ALSO SHOULD REMAIN OFFSHORE EXCEPT NEAR RIVER MOUTH. 

   ...CENTRAL/S TX TO CENTRAL GULF COAST...
   WIDELY SCATTERED TSTMS IN CLUSTERS SHOULD PERSIST THROUGH REMAINING
   DAYLIGHT HOURS...BEFORE WEAKENING OF LIFT AT ALL SCALES LESSENS
   COVERAGE OF SUFFICIENTLY DEEP CONVECTION.  MEANWHILE...LOW-LEVEL WAA
   AND ISENTROPIC LIFT TO LFC WILL SUPPORT CONVECTIVE POTENTIAL FROM NW
   OF SFC LOW TO N OF QUASISTATIONARY FRONT...AMIDST POCKETS OF
   ELEVATED MUCAPE GENERALLY BELOW 500 J/KG.  REINFORCEMENT OF
   LOW-LEVEL STATIC STABILITY FROM PROFUSE PRECIP SHIELD NOW OVER SE TX
   AND LA SHOULD HELP TO KEEP FRONTAL ZONE AND SFC-BASED
   EFFECTIVE-INFLOW PARCELS FROM REACHING INLAND THROUGH PERIOD. 
   THIS...IN COMBINATION WITH WEAK LAPSE RATES ALOFT AND RESULTANT
   MEAGER BUOYANCY...SHOULD LIMIT POTENTIAL FOR STG GUSTS TO REACH SFC.
   WHILE ISOLATED CLICKS OF SMALL HAIL CANNOT BE RULED OUT IN
   DEEPEST/MOST INTENSE CORES...OVERALL SVR POTENTIAL APPEARS TOO
   CONDITIONAL AND MEAGER FOR EVEN MRGL PROBABILITIES ATTM.

   ...NEAR-COASTAL PAC NW...
   MOISTURE-CHANNEL AND IR ANIMATIONS INDICATE SHORTWAVE TROUGH ABOUT
   TO MOVE ASHORE.  SWATH OF LIGHTNING IS DETECTED ATTM INVOF S-CENTRAL
   ORE COAST...AND SEPARATE AREA OF GLACIATED/LOW-TOPPED CONVECTION
   APPEARS ON SATELLITE IMAGERY OFFSHORE NWRN ORE AND WA.  ACCOMPANYING
   DESTABILIZATION WAS SAMPLED BY 12Z UIL RAOB THAT YIELDED AROUND 350
   J/KG MUCAPE AND 200 J/KG MLCAPE...EXTENDING INTO ICING LAYERS
   SUITABLE FOR LTG GENERATION DESPITE SFC TEMPS ONLY IN UPPER 40S F
   THERE AND 50S OVER PAC WATERS.  THIS MRGLLY BUOYANT AIR MASS WILL
   HELP TO MAINTAIN POTENTIAL FOR ISOLATED TO WIDELY SCATTERED THUNDER
   FOR A FEW MORE HOURS...FOLLOWED BY RELATIVE LULL LASTING INTO
   TONIGHT.  SECOND EPISODE OF THUNDER POTENTIAL MAY DEVELOP AFTER
   ABOUT 06Z AS LOW-MIDDLE-LEVEL DESTABILIZATION AND MOISTURE TRANSPORT
   OCCUR AHEAD OF NEXT NERN-PAC PERTURBATION.

   ..EDWARDS/COHEN.. 12/19/2014

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