Severe Thunderstorm Warning 141, NWS New Orleans, LA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS/BATON ROUGE LA
200 AM CST TUE DEC 24 2002

HEAVY WEATHER IS EXPECTED TO CLEAR THE AREA DURING THE MORNING HOURS.

A COLD FRONT IS EXPECTED TO MOVE INTO THE WESTERN PORTION OF THE
AREA AROUND SUNRISE AND MOVE INTO EASTERN ALABAMA BY LATE THIS
AFTERNOON. SURFACE LOW PRESSURE OVER EAST CENTRAL LOUISIANA IS
EXPECTED TO RAPIDLY MOVE NORTHEAST INTO NORTHEAST ALABAMA BY LATE
THIS AFTERNOON. UPPER TROF WILL MOVE ACROSS THE LOWER MISSISSIPPI
VALLEY TONIGHT. MODELS INDICATE THE ATMOSPHERE WILL BEGIN TO RAPIDLY
DRY OUT ABOVE 850 MILLIBARS DURING THE AFTERNOON HOURS. EXPECT TO
SEE SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT WITH ONLY PATCHY
PATCHY LIGHT RAIN AFTER FRONTAL PASSAGE. THURSDAY SHOULD SEE AN
UPPER TROF MOVE ACROSS THE LOWER MISSISSIPPI VALLEY. ENERGY
ASSOCIATED WITH THE TROF WILL REMAIN WELL NORTH OF THE AREA. EXPECT
TO SEE ONLY A MINOR INCREASE IN HIGH CLOUDS AHEAD OF THE TROF.
COLDER AIR WILL SPREAD ACROSS THE AREA AS THE SURFACE LOW PULLS
NORTHEAST. WILL LIKELY SEE A LIGHT FREEZE NORTH OF LAKE
PONTCHARTRAIN AND SOUTHWEST MISSISSIPPI WITH PATCHY FROST IN THE
MISSISSIPPI COASTAL COUNTIES CHRISTMAS NIGHT. SHOULD HAVE MOSTLY
CLEAR SKIES THROUGH THE WEEKEND WITH INCREASING CLOUDINESS ON MONDAY.

MCB 58/34/52/28 6000
BTR 60/38/51/30 6000
MSY 63/43/53/35 7000
GPT 67/39/53/32 8000

.NEW...SMALL CRAFT ADVISORY FROM KPQL TO THE ATCHAFALAYA RIVER BASIN
       OUT 60 NM INCLUDING LAKES PONTCHARTRAIN AND MAUREPAS.
LA...NONE.
MS...NONE.

23

LAZ034>040-046>050-056>070-MSZ068>071-077-080>082-241230-

HAZARDOUS WEATHER OUTLOOK...UPDATED FOR TORNADO WATCH
NATIONAL WEATHER SERVICE NEW ORLEANS LA
630 PM CST MON DEC 23 2002

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST LOUISIANA AND
EXTREME SOUTHWEST AND COASTAL MISSISSIPPI.

.DAY ONE...TONIGHT

...THERE IS A MODERATE TO HIGH RISK OF SEVERE THUNDERSTORMS WITH
DAMAGING WINDS AND TORNADOES TONIGHT...

THUNDERSTORMS...
NUMEROUS SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP ACROSS
THE FORECAST AREA OVERNIGHT. SEVERE THUNDERSTORMS ARE LIKELY AND A
TORNADO WATCH HAS BEEN ISSUED UNTIL 300 AM FOR EXTREME SOUTHWEST
MISSISSIPPI...COASTAL MISSISSIPPI AND ALL OF SOUTHEAST LOUISIANA.
THE PRIMARY CONCERN WILL BE SUPERCELL STORMS CAPABLE OF PRODUCING
TORNADOES...SQUALL LINES WITH DAMAGING WINDS...AND POSSIBLY SOME
DIME SIZED OR LARGER HAIL ASSOCIATED WITH THE STRONGEST STORMS.
LIGHTNING IS EXPECTED TO BE FREQUENT TO CONTINUOUS AT TIMES.
WIDESPREAD HEAVY RAIN IS EXPECTED TO AVERAGE AROUND 2 INCHES OF
ACCUMULATION WITH LOCALLY HIGHER AMOUNTS UP TO 4 INCHES POSSIBLE.
FORECASTED STORM MOTION IS TO THE NORTHEAST AT 40 TO 50 MPH. THE
SEVERE THUNDERSTORM HAZARD WILL BE THROUGH THE NIGHT.

IN ADDITION TO THE THUNDERSTORM THREAT...A SMALL CRAFT ADVISORY IS
IN EFFECT FOR THE GULF COASTAL WATERS OUT 60 NM AND FOR LAKES
PONTCHARTRAIN AND MAUREPAS. SOUTHEAST WINDS AROUND 20 TO 25 KNOTS
ARE EXPECTED TO CONTINUE ACROSS THESE WATERS TONIGHT. BOATERS ARE
URGED TO EXERCISE EXTREME CAUTION AND SEEK SAFE HARBOR IMMEDIATELY
SHOULD THE SITUATION WARRANT.

.DAYS TWO THROUGH SEVEN...

NUMEROUS SHOWERS AND THUNDERSTORMS WILL CONTINUE INTO TUESDAY BEFORE
DIMINISHING DURING THE AFTERNOON HOURS.

SMALL CRAFT ADVISORY CONDITIONS ARE ALSO EXPECTED TO PERSIST THROUGH
TUESDAY WITH WINDS SHIFTING TO THE NORTHWEST AROUND 20 KNOTS WITH
HIGHER GUSTS. WINDS AND SEAS ARE EXPECTED TO SUBSIDE CHRISTMAS DAY.

NO HAZARDOUS WEATHER IS EXPECTED CHRISTMAS DAY AND CONTINUING
THROUGH MONDAY.

.SPOTTER INFORMATION STATEMENT...

THE ACTIVATION OF STORM SPOTTERS...HAM RADIO OPERATORS AND EMERGENCY
MANAGEMENT PERSONNEL...IN SUPPORT OF SEVERE WEATHER OPERATIONS...IS
REQUESTED FOR TONIGHT. EMERGENCY MANAGERS AND FIRST RESPONSE
AGENCIES ARE URGED TO STAFF ACCORDINGLY FOR SEVERE WEATHER
OPERATIONS.

ALL INTERESTS ARE URGED TO STAY TUNED FOR LATER STATEMENTS...WATCHES
AND WARNINGS LATER TODAY AND TONIGHT.