MESOSCALE DISCUSSION 2327
   NWS STORM PREDICTION CENTER NORMAN OK
   0859 PM CST TUE NOV 15 2011
   
   AREAS AFFECTED...PORTIONS CENTRAL/SRN LA...SRN MS...SWRN AL.
   
   CONCERNING...TORNADO WATCH 886...
   
   VALID 160259Z - 160500Z
   
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 886 CONTINUES.
   
   CONTINUE WW ALONG/AHEAD OF PRIMARY/BKN CONVECTIVE BAND.  AREAS E OF
   PRESENT WW WILL BE MONITORED FOR PSBL EXTENSION OR ADDITIONAL WW. 
   COVERAGE OF POTENTIALLY SVR TSTMS WITHIN BROADER CONVECTIVE REGIME
   WILL REMAIN ISOLATED AND MRGL FOR WW...BUT SUPERCELL/TORNADO
   POTENTIAL CANNOT BE RULED OUT.
   
   MAIN TSTM AREA CONTINUES TO SHIFT ENEWD ACROSS CENTRAL/SRN
   LA...EXTENDING AT 230Z FROM ACADIA-VERMILION PARISHES AND THEN SSWWD
   OVER COASTAL/OFFSHORE WATERS.  SEPARATE CLUSTER OF TSTMS WAS MOVING
   NEWD ACROSS WINN/GRANT PARISHES.  INITIALLY SEPARATE BAND OF
   CONVECTION FROM JUST S MCB SWWD ACROSS BTR MAY MERGE WITH NRN
   PORTION OF WRN TSTM BAND.  RISK PERSISTS FOR OCNL/EMBEDDED
   MESOCYCLONES...BRIEF TORNADOES AND A FEW STG-DAMAGING GUSTS WITH ANY
   OF THIS ACTIVITY.  SUPERCELL POTENTIAL ALSO EXISTS IN WARM SECTOR
   EWD ACROSS DISCUSSION AREA...BUT MORE ISOLATED IN COVERAGE.  SVR
   POTENTIAL IS LOWER AWAY FROM MAIN CONVECTIVE AREA...BUT NONZERO
   GIVEN PRESENCE OF FAVORABLE SHEAR/INSTABILITY THROUGH REMAINDER
   EVENING.  TSTM COVERAGE E OF PRIMARY ASCENT ZONE WILL BE LIMITED BY
   LACK OF ROBUST DEEP-LAYER ASCENT AND LOW-LEVEL BOUNDARIES AS FOCI. 
   HOWEVER...HIGH MOISTURE THAT CHARACTERIZES NEAR-COASTAL MARINE LAYER
   WILL STEM DIABATIC SFC COOLING ENOUGH TO MAINTAIN MINIMAL CINH FOR A
   FEW MORE HOURS.  RELATIVE POCKET OF DRY AIR WAS ANALYZED OVER
   CENTRAL/SRN MS ON 00Z 850-925 MB CHARTS...AND IS MANIFEST AT SFC IN
   FORM OF LOW-MID 60S F SFC DEW POINTS AT CBM...MEI...JAN AND PIB. 
   EXPECT DRY HOLE TO ERODE/MOISTEN FROM S-N AMIDST FAVORABLE LOW-LEVEL
   THETAE ADVECTION THROUGH 06Z.  MARINE-SECTOR ENVIRONMENT WILL BE
   CHARACTERIZED BY MLCAPE GENERALLY AROUND 1500 J/KG AND FAVORABLE
   DEEP-LAYER WINDS -- E.G. EFFECTIVE SHEAR MAGNITUDES COMMONLY 50-60
   KT.  WEAK NEAR-SFC WINDS ARE LIMITING SRH ATTM...ALTHOUGH PROGGED
   STRENGTHENING OF LLJ TO AROUND 35 KT BY 06Z SHOULD ENLARGE
   HODOGRAPHS ENOUGH TO SUPPORT POTENTIAL FOR ANY RELATIVELY SUSTAINED
   DISCRETE CELLS TO ROTATE.
   
   ..EDWARDS.. 11/16/2011
   
   
   ATTN...WFO...MOB...JAN...LIX...LCH...SHV...
   
   LAT...LON   29559252 30469239 31739255 31839151 31719012 31788806
               30588784 30258903 29608990 29159077 29389144 29389114
               29559142 29509154 29659163 29379188 29539191 29569217
               29559252