Severe Thunderstorm Warning 476, NWS Jackson, MS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
255 AM CDT MON OCT 07 2002

PRIMARY FORECAST CONCERNS IN SHORT TERM REVOLVE AROUND COLD FRONTAL
PASSAGE AND ASSOCIATED CONVECTIVE PRECIPITATION. FRONTAL PASSAGE
LOOKS TO BE SLOW WITH BOUNDARY EVENTUALLY HANGING UP ALONG THE GULF
COAST TONIGHT. THE OVERALL PATTERN SHOULD REMAIN A BIT ACTIVE
THROUGH THE UPCOMING WEEK AS THE MEAN TROUGH POSITION REMAINS WEST
OF THE LOWER MISSISSIPPI VALLEY REGION...ALLOWING SHORTWAVE ENERGY
TO RIPPLE THROUGH A WEAK GULF COAST BAROCLINIC ZONE. BIGGEST
QUESTIONS AT THIS TIME ARE RELATED TO SPECIFIC SHORTWAVE TROUGHS AND
THEIR AFFECT ON THE FORECAST AREA.

FOR TODAY...CURRENTLY DEALING WITH CONVECTIVE COMPLEX OVER NW HALF
OF THE AREA. LATEST SFC DATA ANALYSIS INDICATES PREFRONTAL TROF
ASSOC WITH COMPLEX INTO NW MS/NE LA...WHILE THE COLD FRONT APPEARS
TO BE MOVING INTO CNTRL AR. BOTH THE 6HR FORECASTS OF THE ETA AND
GFS ARE ON TRACK WITH COLD FRONT...AND BOTH ARE IN GENERAL AGREEMENT
ON MASS FIELDS. BOTH MODELS IMPLY BEST CONVECTIVE PRECIP WILL FALL
DURING THE MORNING OVER CNTRL/ERN PORTIONS OF THE AREA...WITH LESSER
AMOUNTS THIS AFTN AS FRONT PROGRESSES SOUTH INTO GULF COAST MID
LEVEL RIDGE. APPEARS THE GFS GETS A LITTLE TOO AGGRESSIVE WITH LOW
LEVEL COLD ADVECTION LATER TODAY...AND WILL FOLLOW BLEND OF MET/MAV
GUIDANCE FOR TEMPS. WILL MAKE LAST MINUTE DECISION ON PRECIP CHANCES
FOR TODAY...BUT WILL MOST SURELY GO CATEGORICAL FOR PRE-NOON HOURS
FOR SOME OF CNTRL/ERN ZONES DEPENDING ON POSTION OF COMPLEX. LEAST
CHANCE FOR PRECIP SHOULD EXIST OVER NW ZONES WHERE DRY AIR ADVECTION
WILL TAKE PLACE.

FOR TONIGHT THROUGH TUESDAY NIGHT...THESE LOOK TO BE THE QUIETEST
PERIODS OF THE FORECAST WITH WEAK SHORTWAVE RIDGE PROGRESSING OVER
THE REGION. WILL CONTINUE TREND OF DRY WEATHER FOR THESE PERIODS. DO
NOT EXPECT A BIG DROP IN TEMPS EITHER NIGHT AS CLOUD COVER WILL
HINDER RADIATIONAL COOLING PROCESS. IN FACT...BOTH ETA AND GFS KEEP
PRECIP WATER VALUES ABOVE 1.5 INCHES OVER SRN HALF OF AREA.

FOR WEDNESDAY THROUGH FRIDAY...A RELATIVELY WEAK...BUT DISTINCT
SHORTWAVE TROF WILL PROGRESS SLOWLY EAST ACROSS TX TOWARDS THE
FORECAST AREA DURING THIS PERIOD. RAIN CHANCES WILL ONCE AGAIN BE ON
THE INCREASE AS THIS SYSTEM INITIATES WARM/MOIST ADVECTION ALONG THE
STALLED FRONT. GFS DEVELOPS A DISTINCT SOUTHERLY LOW LEVEL JET INTO
WRN PORTIONS OF AREA BY THURSDAY. LOOKS LIKE A TAP FROM HIGH
MOISTURE CONTENT AIRMASS OVER BAY OF CAMPECHE MAY SET UP AT THIS
TIME...WOULDNT BE SUPRISED TO SEE LOCALLY HEAVY RAINFALL AS
SHORTWAVE TROF AXIS PUSHES THROUGH FRIDAY. NO CHANGES ARE PLANNED TO
LATEST FORECAST.

LOOKING AHEAD TO NEXT WEEKEND...GFS CONTINUES TO INDICATE THAT
STRONG HEIGHT FALLS WILL BE DEVELOPING OVER WRN HALF OF THE NATION.
PATTERN MAY KEEP PATTERN UNSETTLED THIS WEEKEND...BUT TOO FAR OUT TO
SAY HOW MUCH RIDGING MAY BE OVER AREA SO WILL KEEP CURRENT DRY
FORECAST GOING.

PRELIM NUMBERS...
JAN 80/60/78/60/80 82123
MEI 80/60/79/58/81 83223

.JAN...
AR...NONE
LA...NONE
MS...NONE

43

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>066-072>074-
071200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE JACKSON MS
757 PM CDT SUN OCT 06 2002

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL MISSISSIPPI...
NORTHEAST LOUISIANA...AND EXTREME SOUTHEAST ARKANSAS

.DAY ONE...

...THUNDERSTORMS...
ISOLATED TO SCATTERED THUNDERSTORMS WILL DEVELOP OVER EXTREME
SOUTHEAST ARKANSAS...NORTHEAST LOUISIANA...AND MUCH OF
MISSISSIPPI AS THE NIGHT CONTINUES. ISOLATED STRONG THUNDERSTORMS
MAY CONTAIN GUSTS UP TO 35 MPH...FREQUENT LIGHTNING STRIKES...AND
LOCALLY VERY HEAVY RAINS. HOWEVER... SEVERE THUNDERSTORMS ARE NOT
EXPECTED.

THUNDERSTORM COVERAGE WILL INCREASE LATER TONIGHT FROM THE
NORTHWEST...AS A COLD FRONT PUSHES TOWARD THE LOWER MISSISSIPPI
RIVER VALLEY. THIS SIGNIFICANT COLD FRONT WILL MOVE STEADILY
SOUTHEAST AND INTO THE FORECAST AREA BY 3 AM MONDAY MORNING.

.SPOTTER CALL TO ACTION STATEMENT...
THE ACTIVATION OF STORM SPOTTERS...HAM RADIO OPERATORS...AND
EMERGENCY MANAGEMENT PERSONNEL IN SUPPORT OF SEVERE WEATHER
OPERATIONS...IS NOT ANTICIPATED THROUGH TONIGHT.

.DAYS TWO THROUGH SEVEN...
NO HAZARDOUS WEATHER IS EXPECTED THROUGH THE PERIOD.

FOR MORE INFORMATION PLEASE VISIT OUR WEBSITE AT
WWW.SRH.NOAA.GOV/JAN. THIS INCLUDES THE GRAPHICAL HAZARDOUS
WEATHER OUTLOOK.