Severe Storm Outlook Narrative (AC)
Issued by NWS

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000
ACUS11 KWNS 040719
SWOMCD
SPC MCD 040718
MSZ000-LAZ000-041015-

MESOSCALE DISCUSSION 1865
NWS STORM PREDICTION CENTER NORMAN OK
0118 AM CST SUN DEC 04 2016

AREAS AFFECTED...MUCH OF SOUTHEASTERN LA NORTHEASTWARD TOWARD
COASTAL MS

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 040718Z - 041015Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...THUNDERSTORMS MAY INCREASE IN COVERAGE AND INTENSITY THIS
MORNING...IN ASSOCIATION WITH A WARM FRONT AND MAINLY AHEAD OF THE
ADVANCING SQUALL LINE. A WEAK TORNADO OR TWO WILL BE CONDITIONALLY
POSSIBLE...ALONG WITH LOCALIZED GUSTY WINDS.

DISCUSSION...SURFACE ANALYSIS SHOWS THAT PORTIONS OF A WARM FRONT
HAVE MOVED ASHORE COASTAL SOUTHEASTERN LA WITH 69 TO 72 F DEWPOINTS
OBSERVED AT 07Z. A NORTHWARD ADVANCEMENT OF THIS BOUNDARY IS
EXPECTED THROUGH MORNING...JUST AHEAD OF A LUMBERING SQUALL LINE
CONTAINING GUSTY WINDS...WITH A MARGINALLY UNSTABLE AIR MASS
DEVELOPING. MODELS DIFFER...BUT IN GENERAL SUGGEST AT LEAST 500 J/KG
MUCAPE MAY DEVELOP INLAND...WITH SOME SOLUTIONS SUGGESTING 1000 J/KG
ALONG THE LA/MS COASTS BY 12Z. IF SUFFICIENT INSTABILITY CAN SPREAD
INLAND...300-400 M2/S2 SRH WOULD SUPPORT A FEW SMALL SUPERCELLS WITH
BRIEF/WEAK TORNADO RISK.

INDEED...RADAR TRENDS AS OF 07Z ALREADY SHOW A FEW SMALL CELLS WITH
ROTATION EAST OF ST. BERNARD PARISH OVER THE WATER...LIKELY ELEVATED...
WITH A LARGER STORM NOTED JUST SOUTH OF KXPY IN SOUTHERN LAFOURCHE
PARISH...LIKELY SURFACE BASED.

TRENDS WILL CONTINUE TO BE MONITORED FOR A POSSIBLE DEVELOPING WEAK
TORNADO THREAT THIS MORNING.

..JEWELL/EDWARDS.. 12/04/2016

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

ATTN...WFO...LIX...LCH...

LAT...LON   29529176 29869101 30068998 30558900 30478852 30288841
            29648876 29058895 28948930 28969023 28999089 29209179
            29529176



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