Hail in Louisiana, May 30, 2002

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS/BATON ROUGE LA
315 AM CDT THU MAY 30 2002

WILL BE BRIEF AS ONGOING WEATHER QUITE ACTIVE. PLAN ON MAINTAINING
HIGH POPS FOR TODAY AND INTO THIS EVENING WITH A SPLIT POP FOR THE
SECOND GROUP TO SHOW GENERAL IMPROVEMENT BY MIDNIGHT. THEREAFTER...A
GENERAL DOWNTREND TO 30 PERCENT FOR FRIDAY AND ISOLATED
AFTERNOON/EARLY EVENING THEREAFTER. TEMPS OF GUIDANCE LOOK GOOD BUT
WILL UNDERCUT TODAY IN SOME LOCATIONS FOR EXTENSIVE CLOUDINESS AND
RAINFALL CONSIDERATIONS.

MODELS...PARTICULARLY THE AVN...INDICATING CUT-OFF LOW SINKING
SOUTHWARD INTO THE GULF IN TIME WITH A COOL THICKNESS POOL OVER OUR
CWA IN THE FACE OF ONSHORE FLOW. THIS IS A TYPICAL TRADEMARK OF
HEAVY RAINFALL. WILL BE UPDATING URBAN AND SMALL STREAM FLOOD
ADVISORY FOR THE MISSISSIPPI COASTAL COUNTIES SOON. WILL BE ADDING
VALUE TO FORECAST BY USING LOCAL RICKS INDEX/PRECIPITATION
CALCULATOR OUTPUT BASED ON 18Z-00Z AVN FORECAST SOUNDINGS USING 335K
AS THE CRITICAL LIFT.

PCPN CALCULATOR OUTPUT VALID 18Z THROUGH 00Z TODAY...335K LIFTED
FROM 912 MB: POP 46%...PCPN 1.80...POTL 4.69 FOR TEMPS BELOW
71F...FMAP 0.96...RICKS INDEX 128...PROB SVR 0%...GUSTS 42-52
KT...HAIL 0.67 (PEA-MARBLE)...TOR NONE. IF 335K ATTAINED AT 850 MB
THEN POP 100%...FMAP 2.09...PROB SVR 14%. THIS WOULD INDICATE A
MARGINAL SEVERE DAY AND WILL BE HANDLED AS SUCH IN THE HAZARDOUS
WEATHER OUTLOOK. THE MAIN CONCERN WILL BE THE FLOOD POTENTIAL DUE TO
EXCESSIVE RAINFALL. WILL INDICATE 2 TO 3 INCHES LOCALLY UP TO 5
INCHES POSSIBLE MAINLY ALONG THE MISSISSIPPI COAST INITIALLY THEN
FARTHER NW INTO SW MS LATER THIS AFTERNOON.

MCB 79/64/87/65 7631         BTR 83/66/87/66 7631
MSY 83/68/86/70 6231         GPT 82/69/86/69 6231

.NEW...NONE.
LA...NONE.
MS...NONE.
24

LAZ034>040-046>050-056>070-MSZ068>071-077-080>082-311100-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1100 AM CDT THU MAY 30 2002

.SYNOPSIS...A WEAK SURFACE TROUGH OF LOW PRESSURE WILL CONTINUE TO
DRIFT SOUTH ACROSS SOUTHEAST LOUISIANA AND SOUTH MISSISSIPPI THIS
AFTERNOON AND EVENING. THIS TROUGH WILL INTERACT WITH AN UPPER
LEVEL DISTURBANCE MOVING SOUTHWARD OVER LOUISIANA TO PRODUCE NUMEROUS
SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND THIS EVENING.

.THUNDERSTORMS...
NUMEROUS THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON
AND PERSIST INTO THE EVENING HOURS BEFORE DIMINSIHING OVERNIGHT. IN
ADDITION TO FREQUENT LIGHTNING...SOME OF THE STRONGER THUNDERSTORMS
MAY PRODUCE STRONG GUSTY WINDS OF 40 TO 50 MPH...PEA TO MARBLE SIZE
HAIL...AND LOCALLY HEAVY DOWNPOURS OF RAIN. RAINFALL AMOUNTS OF ONE
TO TWO INCHES WILL BE COMMON WITH THE STRONGER THUNDERSTORMS WITH
ISOLATED THREE TO FOUR INCH AMOUNTS POSSIBLE. LOCALIZED FLOODING OF
ROADWAYS AND LOW LYING AREAS WILL BE POSSIBLE WITH SOME OF THE
STORMS.

.ACTIONS...
NONE AT THIS TIME.

FOR MORE INFORMATION...VISIT OUR WEB SITE AT WWW.SRH.NOAA.GOV/LIX
(ALL LOWER CASE).