Severe Storm Outlook Narrative (AC)
Issued by NWS

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000
ACUS11 KWNS 232006
SWOMCD
SPC MCD 232006
GAZ000-FLZ000-ALZ000-MSZ000-232200-

MESOSCALE DISCUSSION 1987
NWS STORM PREDICTION CENTER NORMAN OK
0206 PM CST TUE DEC 23 2014

AREAS AFFECTED...PORTIONS OF SRN-CNTRL AL AND THE WRN FL PANHANDLE

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 232006Z - 232200Z

PROBABILITY OF WATCH ISSUANCE...80 PERCENT

SUMMARY...THUNDERSTORMS WILL INCREASE IN COVERAGE AND INTENSITY LATE
THIS AFTERNOON INTO THIS EVENING...WITH A RESULTANT INCREASE IN THE
POSSIBILITY FOR DAMAGING WINDS AND A FEW TORNADOES.

DISCUSSION...AS FORCING FOR ASCENT INCREASES DUE TO AN
EWD-PROGRESSING COLD FRONT IN CONJUNCTION WITH A STRENGTHENING LLJ /
WAA ALOFT...SHOWERS AND THUNDERSTORMS ARE EXPECTED TO INCREASE
ACROSS THE AREA LATE THIS AFTERNOON AND EVENING. BREAKS IN CLOUD
COVER...ESPECIALLY NEAR THE GULF COAST...HAVE RESULTED IN IMPROVED
INSOLATION AND INCREASING BUOYANCY. WHILE MLCAPE VALUES ARE STILL
MEAGER /AROUND 250-500 J PER KG/...NEWD ADVECTION OF HIGHER THETA-E
VALUES AND 1-2 MORE HOURS OF INSOLATION WILL RESULT IN MLCAPE VALUES
APPROACHING 1000 J PER KG. ADDITIONALLY...THE STRENGTHENING
BACKGROUND FLOW FIELD WILL CONTRIBUTE TO EFFECTIVE DEEP-LAYER SHEAR
VALUES INCREASING TO AROUND 50-60 KTS ACROSS THE AREA. IN
COMBINATION WITH INCREASING EFFECTIVE SRH AND A MOIST BL
CHARACTERIZED BY MEAN MIXING RATIOS UPWARDS OF 13-14 G/KG...A
MIXTURE OF CONVECTIVE MODES CAPABLE OF DAMAGING WINDS AND A FEW
TORNADOES WILL LIKELY CONTINUE EWD DOWNSTREAM OF WW560. AS
SUCH...ISSUANCE OF A NEW WATCH IS LIKELY LATE THIS AFTERNOON.

..PICCA/CORFIDI.. 12/23/2014

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...TAE...BMX...MOB...LIX...

LAT...LON   29928587 30058698 30098841 32648819 33218814 33698796
            33618647 33058555 31788510 30488542 29928587



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