[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 200842
SWOMCD
SPC MCD 200842 
LAZ000-201115-

MESOSCALE DISCUSSION 0316
NWS STORM PREDICTION CENTER NORMAN OK
0242 AM CST SUN MAR 20 2005

AREAS AFFECTED...COASTAL LA AND ADJACENT WATERS -- FROM SERN CAMERON
TO TERREBONNE PARISHES

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 200842Z - 201115Z

NRN PORTION OF PERSISTENT/WELL-DEFINED BOW ECHO IS MOVING ENEWD
40-50 KT ACROSS GULF WATERS SE OF SABINE PASS...AND MAY AFFECT
DISCUSSION AREA BETWEEN 930-12Z.  SEVERE POTENTIAL INCREASES WITH
SWD EXTENT OVER COASTAL AREAS AND INTO GULF...WITH DAMAGING GUSTS
POSSIBLE.  WW NOT EXPECTED ATTM BECAUSE OF LIMITED COVERAGE OF
THREAT OVER LAND.

SFC ANALYSIS INDICATES MARINE FRONT -- DENOTING NRN EDGE OF MOST
HIGHLY MODIFIED GULF AIR -- FROM ABOUT 75 S MSY WNWWD TO ABOUT 60
SSE LCH...DRIFTING N. THIS FRONT MAY BARELY MOVE INLAND OVER
PORTIONS VERMILION/IBERIA/ST MARY/TERREBONNE PARISHES BEFORE PASSAGE
OF MCS...ALLOWING NEARLY SFC-BASED BUOYANCY WITH MUCAPES 1000-1500
J/KG.  GREATEST SEVERE POTENTIAL THEREFORE IS ALONG IMMEDIATE
COASTAL AREAS AND SWD OVER GULF WATERS.  RISK FOR DAMAGING
DOWNDRAFTS TO PENETRATE TO SFC DECREASES NWD OVER PROGRESSIVELY
DEEPER NEAR-SFC STABLE LAYER.  IN ADDITION TO FAVORABLE INFLOW-LAYER
THERMODYNAMICS...ACTIVITY SHOULD BE SUPPORTED BY MCV EVIDENT AT 830Z
ABOUT 35 S BPT...AND BY EXTENSIVE LOW-MIDLEVEL REAR-INFLOW JET OF
35-50 KT EVIDENT IN LCH VELOCITY DATA.

..EDWARDS.. 03/20/2005

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

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

29619335 29809301 29949234 29949172 29789125 29609089
29469063 29299044 28929045 28709082 28529116 28419159
28419191 28439244 28379282 28359319 28759298 29159302
29459324 

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