Special Marine Warning 21, NWS New Orleans, LA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1056 AM CDT FRI APR 21 2006

.UPDATE...
MESOSCALE ANALYSIS TRENDS SHOW A RAPID INCREASE IN LOW LEVEL
MOISTURE AND ASSOCIATED INSTABILITY AS SURFACE TEMPERATURES HIT
THE TRIGGER TEMPERATURE OF 80-81 DEGREES. MANY FACTORS ARE COMING
TOGETHER TO SUPPORT SUSTAINED THUNDERSTORM DEVELOPMENT AND STRONG
TO SEVERE THUNDERSTORMS WITH DAMAGING STRAIGHT LINE WINDS.

SEVERE THUNDERSTORM WATCH NUMBER 232 HAS BEEN ISSUED AND IS VALID
UNTIL 4 PM CDT FOR MOST OF THE FORECAST AREA EXCEPT HARRISON AND
JACKSON COUNTIES IN MS. MCS OVER NORTHERN/WESTERN LA IS HOLDING
ITS OWN...AND RADAR SHOWS ADDITIONAL DEVELOPMENT IN THE UNSTABLE
AIR AND REMNANT OUTFLOW BOUNDARY EAST CENTRAL AND SOUTH CENTRAL
LA. SEVERE WEATHER FROM A COMBINATION OF BOWING LINE SEGMENTS AND
SUPERCELL THUNDERSTORMS IS EXPECTED DURING THE NEXT SEVERAL
HOURS...THEN THE ACTIVITY SHOULD TRANSITION TO MOSTLY BOWING LINE
SEGMENTS LATER IN THE AFTERNOON. DAMAGING WINDS ARE THE MAIN
THREAT WITH A SMALL CHANCE OF LARGE HAIL AND ISOLATED TORNADOES.

&&

.AVIATION...
STRONG TO SEVERE THUNDERSTORMS MAY IMPACT THE MCCOMB AND BATON
ROUGE AIRPORTS AND SURROUNDING AREAS DURING THE NEXT FEW HOURS
WITH STRONGER ACTIVITY REACHING THE AIRPORTS AROUND LAKE
PONTCHARTRAIN GENERALLY AFTER 2 PM.

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&

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HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1148 AM CDT FRI APR 21 2006

LAZ034>040-046>050-056>070-MSZ068>071-077-080>082-212300-
AMITE-ASCENSION-ASSUMPTION-EAST BATON ROUGE-EAST FELICIANA-HANCOCK-
HARRISON-IBERVILLE-JACKSON-LIVINGSTON-LOWER JEFFERSON-
LOWER LAFOURCHE-LOWER PLAQUEMINES-LOWER ST BERNARD-LOWER TERREBONNE-
ORLEANS-PEARL RIVER-PIKE-POINTE COUPEE-ST CHARLES-ST HELENA-ST JAMES-
ST JOHN THE BAPTIST-ST TAMMANY-TANGIPAHOA-UPPER JEFFERSON-
UPPER LAFOURCHE-UPPER PLAQUEMINES-UPPER ST BERNARD-UPPER TERREBONNE-
WALTHALL-WASHINGTON-WEST BATON ROUGE-WEST FELICIANA-WILKINSON-
1120 AM CDT FRI APR 21 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST
LOUISIANA AND SOUTHERN MISSISSIPPI.

.DAY ONE...THIS AFTERNOON AND TONIGHT

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS TODAY. STRONG TO
LOCALLY SEVERE THUNDERSTORMS WILL MOVE ACROSS MOST OF EAST CENTRAL
AND SOUTHEAST LOUISIANA AND SOUTH MISSISSIPPI THROUGH EARLY
EVENING. THE MAIN THREATS FROM SEVERE THUNDERSTORMS WILL BE DAMAGING
STRAIGHT LINE WINDS AND FREQUENT LIGHTNING. A FEW OF THE STRONGEST
STORMS COULD PRODUCE LARGE HAIL.

A COLD FRONT WILL MOVE ACROSS THE AREA AND END THE THREAT OF SEVERE
WEATHER FROM WEST TO EAST DURING THE MID AFTERNOON TO EARLY EVENING
HOURS.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS REQUESTED FOR THIS AFTERNOON. A SEVERE
THUNDERSTORM WATCH IS IN EFFECT FOR SOUTHEAST LOUISIANA AND MUCH OF
SOUTHERN MISSISSIPPI THROUGH 4 PM CDT. FIRST RESPONDERS AND STORM
SPOTTERS ARE URGED TO CLOSELY MONITOR THE WEATHER AND CALL IN ANY
SEVERE STORM REPORTS INTO THE NATIONAL WEATHER SERVICE OFFICE IN
SLIDELL LOUISIANA. THE PUBLIC SHOULD RELAY ANY REPORTS INTO THEIR
LOCAL LAW ENFORCEMENT AGENCY FOR RELAY TO THE NATIONAL WEATHER
SERVICE. PERSONS CAN ALSO ENTER STORM REPORTS ON OUR WEBSITE AT
WWW.SRH.NOAA.GOV/LIX (ALL LOWER CASE).

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