Severe Thunderstorm Warning 93, NWS New Orleans, LA

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE NEW ORLEANS/BATON ROUGE LA
1125 AM CDT SUN MAY 11 2003

ALL IN ALL...THE EARLY MORNING GRIDS AND TEXT PRODUCTS LOOK
REASONABLE. THE MAIN CONCERNS FOR THIS UPDATE ARE THE TIMING AND
COVERAGE OF SHOWERS AND THUNDERSTORMS TODAY ALONG WITH SEVERE
POTENTIAL. MODIFIED SOUNDINGS FOR MAX TEMPS OF 85 TO 90 AND PW/S
INCREASING INTO THE 1.75 TO 2 INCH RANGE PRODUCE A VERY UNSTABLE AND
MOIST LOOKING PROFILE. GOES-12 PW SOUNDER DATA SUPPORTS A NARROW
ZONE OF NEAR 2 INCH PW/S COINCIDENT WITH THE LINE OF CONVECTION.
THESE POSITIVE PARAMETERS FOR CONVECTION WILL BE OFFSET QUITE A BIT
BY CLOUD COVER AND THE CAP EARLY ON...AND DECREASING UPPER LEVEL
DIVERGENCE AND UPPER LEVEL SUPPORT AS WE HEAD THROUGH THE AFTERNOON.
ANY SHEAR WILL BE OF THE SPEED VARIETY AS WINDS BECOME INCREASINGLY
UNIDIRECTIONAL WITH HEIGHT THIS AFTERNOON. THE NET RESULT...WILL
KEEP POPS AS IS IN THE 20 TO 30 PERCENT RANGE TODAY. A NORTH TO
SOUTH ORIENTED BAND OF THUNDERSTORMS OR BOW ECHO WOULD BE ABLE TO
PRODUCE STRONG DOWNBURST WINDS GIVEN THE STRONG MID LEVEL WINDS...
BUT THIS IS A LOW PROBABILITY GIVEN THE EXPECTED LOW COVERAGE OF THE
CONVECTION. HAVE MAINTAINED THE POSSIBILITY OF ISOLATED SEVERE
THUNDERSTORMS IN THE HAZARDOUS WEATHER OUTLOOK FOR THE NORTHERN TWO
TIERS OF ZONES.

CLOUDS SHOULD KEEP TEMPERATURES A BIT COOLER NEAR THE CONVECTIVE
BAND IN THE NORTH AND WEST ZONES TODAY. NOT MUCH CONVECTION WILL
CARRY OVER AFTER 7 PM IN THE TONIGHT PERIOD...BUT WILL KEEP 20
PERCENT IN FOR THE EXTREME EAST AND SOUTH ZONES FOR THE EARLY
EVENING. ALSO...CLOUDS SHOULD DECREASE TO PARTLY CLOUDY LATE
TONIGHT. THESE CHANGES WILL BE REFLECTED IN UPDATED GRIDS...
GRAPHICAL AND TEXT PRODUCTS SHORTLY.

UPDATED FIRST AND SECOND PERIOD NUMBERS...

MCB BB 084/060 085/057 083 300
BTR BB 087/064 085/059 083 300
MSY BB 089/071 087/066 085 220
GPT BB 088/069 084/059 083 320

.NEW...NONE.
LA...NONE.
MS...NONE.

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HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1115 AM CDT SUN MAY 11 2003

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

.DAY ONE...TODAY AND TONIGHT

SCATTERED SHOWERS AND THUNDERSTORMS...JUST AHEAD AND ALONG A COLD
FRONT...WILL MOVE ACROSS EXTREME SOUTH MISSISSIPPI AND ADJACENT EAST
CENTRAL LOUISIANA PARISHES NORTH OF BATON ROUGE THROUGH THE EARLY
AFTERNOON HOURS. ACTIVITY IS EXPECTED TO DEVELOP ACROSS THE
REMAINDER OF EAST CENTRAL AND SOUTHEAST LOUISIANA...NORTH OF
INTERSTATE 10 AND LAKE PONTCHARTRAIN INCLUDING THE MISSISSIPPI COAST
DURING THE MID TO LATE AFTERNOON HOURS. ISOLATED SHOWERS AND
THUNDERSTORMS ARE EXPECTED SOUTH OF INTERSTATE 10 AND LAKE
PONTCHARTRAIN. THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS
AFTERNOON ACROSS EXTREME SOUTH MISSISSIPPI AND EAST CENTRAL
LOUISIANA...NORTH OF LINE FROM BATON ROUGE TO PICAYUNE. THE PRIMARY
RISK FROM THESE STORMS WILL BE DAMAGING STRAIGHT LINE WINDS. AS THE
COLD FRONT PUSHES SOUTH...THE UPPER LEVEL ENERGY IS EXPECTED TO PULL
TO THE NORTH AND REDUCE THE RISK OF SEVERE THUNDERSTORMS ACROSS
COASTAL MISSISSIPPI AND SOUTHEAST LOUISIANA LATE THIS AFTERNOON AND
TONIGHT.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

THE AIRMASS WILL BE STABLE AND LESS HUMID MONDAY AND TUESDAY. SOUTH
WINDS WILL RETURN TUESDAY NIGHT CREATING AN UNSTABLE AIRMASS ACROSS
SOUTH MISSISSIPPI AND SOUTHEAST LOUISIANA. SEVERAL UPPER LEVEL
DISTURBANCES ARE EXPECTED TO APPROACH THE AREA FROM THE NORTHWEST
LATE TUESDAY THROUGH EARLY THURSDAY. STRONG THUNDERSTORMS ARE
EXPECTED TO DEVELOP AND AFFECT EXTREME SOUTH MISSISSIPPI...COASTAL
MISSISSIPPI AND PORTIONS OF EAST CENTRAL LOUISIANA NORTH OF LAKE
PONTCHARTRAIN TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. OTHERWISE...NO
HAZARDOUS WEATHER IS EXPECTED MONDAY THROUGH SATURDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER NETWORKS AND EMERGENCY MANAGEMENT AGENCIES SHOULD STAY TUNED
FOR THE LATEST DEVELOPMENTS THIS AFTERNOON...IN CASE ACTIVATION
BECOMES NECESSARY.