Severe Thunderstorm Warning 843, NWS Jackson, MS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
330 PM CST SAT DEC 22 2001

MAIN CONCERNS WILL BE WITH THE TSRA TONIGHT...THEN COLD TEMPS FOR
THE REST OF THE WEEK.

TONIGHT POPS WILL BE STRAIGHT FORWARD...100 PERCENT ALL ZONES...THE
PROBLEM COMES IN WITH THE AMOUNT OF RAIN AND INTENSITY OF STORMS.
FIRST THE AMOUNTS. WILL HOLD OFF ON ANY FFA AS RAIN TOTALS LOOK TO
BE AROUND 1 IN WITH THE BULLSEYE LOOKING TO BE OVER CENTRAL AND EAST
CENTRAL ZONES. HERE...RIVERS ARE NOT AT CRITICAL LEVELS AND SHOULD
BE ABLE TO HANDLE 1 IN AVG RAINFALL. INTENSITY. WILL NOT MENTION
SEVERE IN IN ZONES AT THIS TIME...BUT CAN NOT RULE OUT AN ISOLATED
SVR TSRA SOUTH OF I-20. INSTABILITY WILL BE MARGINAL...BUT WE WILL
BE IN AN AREA OF A COUPLED UPPER JET STRUCTURE...DECENT LAPSE RATES
AND STRONG LL SHEAR. CURRENT THINKING IS THAT MARGINAL HAIL WILL BE
THE MAIN THREAT DUE TO COLD MID AND UPPER LEVEL TEMPS. ALSO...WITH
STRONG LL SHEAR...AN ISOLATED TOR CANT BE RULED OUT. THIS WILL
MAINLY BE OVER THE EXTREME SOUTHERN ZONES WHERE INSTABILITY WILL BE
THE GREATEST.

BY SUN FRONT WILL BE EAST OF CWA. WILL HOLD ON TO 20 POPS CENTRAL
...40/50 EAST AND SE...AS LIGHT RAIN SHOWERS PERSIST IN THE
MORNING. WILL INCLUDE CLEARING TREND BY SUN AFTERNOON AS STRONG
SUBSIDENCE TAKES OVER AND THE COLD AIR MOVES IN. CAA WILL ALLOW FOR
LL THETA SFCS TO RISE BUT THE DOWNWARD MOTION AND DRYING ALOFT WILL
MOVE CLDS OUT BY AFTERNOON. TEMP FORECAST WILL BE TRICKY AS THERE
WILL NOT BE MUCH OF A RANGE. MORNING LOWS WILL DEPEND GREATLY ON HOW
FAR EAST THE FRONT WILL GET BY 12Z. DAYTIME TEMPS WILL HOLD STEADY
AS CAA KICKS IN AND SUNSHINE BREAKS OUT. FORECASTED HIGHS COULD BE
GOOD OR REAL BAD

REST OF PACKAGE WILL CONTINUE TO BE COLD. LOWS GENERALLY IN THE
20S...HIGHS IN THE 40S. MEX GUIDANCE CONTINUES TO GET COLDER...AS IT
INTRODUCED UPPER TEENS FOR MID WEEK. WILL NOT GO THAT LOW YET...WILL
WAIT FOR SOME CONSISTENCY. COLD AIR LOOKS TO REMAIN FOR QUITE SOME
TIME AS GATES WILL CONTINUE TO BE OPEN TO SIBERIA

JAN 50/53/27/46/23 +200
MEI 53/55/28/47/23 +400

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

36

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>066-072>074-
231200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE JACKSON MS
328 PM CST SAT DEC 22 2001

...THUNDERSTORMS...
THUNDERSTORMS WILL SPREAD ACROSS EXTREME SOUTHEAST
ARKANSAS...NORTHEAST LOUISIANA...AND MUCH OF MISSISSIPPI AHEAD OF
A STRONG COLD FRONT EXPECTED TO CROSS THE OUTLOOK AREA OVERNIGHT.
ISOLATED SEVERE THUNDERSTORMS WILL BE POSSIBLE OVER PORTIONS OF
NORTHEAST LOUISIANA AND SOUTH MISSISSIPPI...ESPECIALLY TO THE
SOUTHWEST OF A BASTROP LOUISIANA TO PORT GIBSON TO HATTIESBURG
MISSISSIPPI LINE. THE MAIN SEVERE WEATHER THREAT THIS EVENING
WILL BE FOR LARGE HAIL UP TO THE SIZE OF NICKELS...BUT AS
INSTABILITY INCREASES...DAMAGING WIND GUSTS TO 60 MPH AND
ISOLATED TORNADOES WILL BECOME POSSIBLE...ESPECIALLY ALONG AND
SOUTH OF HIGHWAY 84 FROM NATCHEZ TO HATTIESBURG. AS THUNDERSTORMS
PROGRESS INTO NORTH AND EASTERN MISSISSIPPI...INSTABILITY IS NOT
EXPECTED TO BE AS GREAT...AND SEVERE THUNDERSTORMS ARE NOT
EXPECTED.

EMERGENCY MANAGEMENT PERSONNEL AND STORM SPOTTER ACTIVATION MAY
BE REQUIRED TONIGHT OVER NORTHEAST LOUISIANA AND SOUTH
MISSISSIPPI.

...FLOODING...
LOCALLY HEAVY RAINFALL WILL OCCUR TONIGHT ACROSS EXTREME
SOUTHEAST ARKANSAS...NORTHEAST LOUISIANA...AND MUCH OF
MISSISSIPPI AS THUNDERSTORMS MOVE OVER THE REGION. GROUND
MOISTURE IS HIGH AND IT WILL NOT TAKE MUCH RAIN TO CAUSE RUN-OFF
AND MINOR FLOODING OF LOW-LYING AREAS AND STREETS.
OVERALL...TOTAL RAINFALL AMOUNTS OF ONE TO TWO INCHES WILL BE
POSSIBLE.

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