Severe Thunderstorm Warning 72, NWS New Orleans, LA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS/BATON ROUGE LA
400 AM CDT THU APR 24 2003

VERY INTERESTING WEATHER SCENARIO SETTING UP FOR TODAY. SIGNIFICANT
DISCONTINUITY FOUND IN MODEL QPF FIELDS. WILL BEGIN WITH CURRENT
WEATHER AND MOVE TO WHICH MODEL IS INITIALIZING BEST AND WHICH WE
WILL GO WITH.

VERY STRONG DIRECTIONAL DIVERGENCE FOUND AT 300MB THIS MORNING WITH
PROFILER DATA. THE POINT OR BEGINNING OF THE SPLIT FLOW IS LOCATED
SOUTHEAST OF DALLAS TX NEAR PALESTINE TX. CURRENTLY THERE IS A NEW
AREA OF SH/TS DEVELOPING OVER THIS AREA. THIS LINE WILL BE THE ONE
TO WATCH THROUGH THE MORNING. THE DYNAMICS RESPONSIBLE WILL BE
MOVING OVER LOUISIANA THROUGH THE DAY. SH/TS REALLY EXPLODE LATER
THIS MORNING AND EARLY AFTERNOON INTO A SEVERE TS AND FLOODING EVENT
FOR FOLKS MAINLY NORTH OF THE AREA. ANOTHER AREA OF TS WILL CONTINUE
TO DEVELOP IN THE NW GULF AND MOVE ENE. THESE TWO AREAS OF SH/TS MAY
COUPLE LATE TODAY BRINGING SOME VERY HEAVY RAINFALL TO MANY FOLKS IN
SOUTHERN MISSISSIPPI AS WELL AS THE SE LA AREAS. THIS MAY BEGIN AS
STRONG TO SEVERE TS BEFORE TAPERING INTO A RAIN EVENT LATER TODAY.

THINGS SHOULD COME TOGETHER NICELY TODAY FOR A FEW SEVERE TS ACROSS
THE AREA. 850MB WINDS INCREASE TODAY TO 40-50 KTS BETWEEN 18 AND
00Z. HEATING AND STRONG DIR DIV FIELD AT 300MB WILL BE IN PLACE. A
MODERATE VORT WILL ALSO BE SWINGING DOWN TO MEET THE UNSATBLE AIR
MASS AT THE SAME TIME. BELIEVE THIS IS WHEN THE REAL FIRE WORKS WILL
BEGIN. LONG STORY SHORT...NOT MUCH MORE THAN GARDEN VARIETY SH/TS
THIS MORNING. MAIN ATTENTION WILL BE FOCUSED TOWARD AFTERNOON AND
EVENING ESPECIALLY FROM LAKES NORTHWARD. THESE LOOK ATTM TO BE
MAINLY HAIL AND DAMAGING WINDS BUT WITH 2000+CAPE AND STRONG SPEED
SHEAR OFF THE SFC WOULDNT BE SURPRISED TO SEE AN ISOLATED TOR WITH
THE POINT OF MOST SOUTHERN EXTENDED CELLS WHERE STORM RELATIVE WINDS
AND VORTICITY WILL BE MAXIMIZED.

WILL GO WITH A MIX OF BOTH ETA AND AVN ON QPF. BOTH ARE TRYING TO
PICK UP ON QPF REGIONS SINCE BOTH AREAS OF PRECIP SHOULD BE VALID.

***PRELIM NUMBERS***
MCB 78/65/85/54 8400
BTR 79/67/84/56 8400
MSY 79/69/84/63 7521
GPT 76/68/81/63 7622

.NEW...SMALL CRAFT ADVISORY FOR ALL COASTAL ZONES AND LAKES.
LA...NONE.
MS...NONE.

17

LAZ034>040-046>050-056>070-MSZ068>071-077-080>082-251100-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1000 AM CDT THU APR 24 2003

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

.DAY ONE...THIS AFTERNOON AND TONIGHT

SCATTERED TO NUMEROUS THUNDERSTORMS ARE EXPECTED THIS AFTERNOON AND
TONIGHT AS A STRONG UPPER LEVEL SYSTEM AFFECTS THE AREA. THERE IS A
SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND THIS EVENING.
THE MAIN HAZARD FROM SEVERE THUNDERSTORMS WILL BE DAMAGING WINDS AND
LARGE HAIL...AN ISOLATED TORNADO IS ALSO POSSIBLE. THE MOST LIKELY
AREAS TO SEE THIS ACTIVITY WILL BE FROM LAKES MAUREPAS TO
PONTCHARTRAIN NORTHWARD OR NORTH OF INTERSTATE 10.

MARINE...
SMALL CRAFT ADVISORIES ARE IN EFFECT FOR ALL COASTAL WATERS
INCLUDING LAKES MAUREPAS AND PONTCHARTRAIN FOR WINDS 20 TO 25 KNOTS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

NO HAZARDOUS WEATHER IS EXPECTED THROUGH WEDNESDAY.

.SPOTTER INFORMATION STATEMENT...

ACTIVATION OF STORM SPOTTERS...HAM RADIO OPERATORS AND EMERGENCY
MANAGEMENT PERSONNEL...IN SUPPORT OF SEVERE WEATHER OPERATIONS...MAY
BE REQUIRED THIS AFTERNOON.