Severe Thunderstorm Warning 623, NWS Jackson, MS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
305 PM CDT MON AUG 20 2001

THE LATEST UPPER AIR ANALYSIS AND WATER VAPOR SATELLITE IMAGERY
SHOWS MOISTURE WRAPPING AROUND A 500 MB LOW OVER EASTERN MICHIGAN. A
500 MB TROUGH EXTENDS SOUTHWARD INTO MISSISSIPPI. A WEAK SURFACE
BOUNDARY IS IN PLACE ACROSS NORTH CENTRAL MISSISSIPPI. ISOLATED
STRONG TO SEVERE THUNDERSTORMS ARE ERUPTING THIS AFTERNOON ACROSS
NORTH CENTRAL PORTIONS OF THE FORECAST AREA ALONG THE SURFACE FRONT
AND ALONG THE EDGE OF THE UPPER AIR MOISTURE GRADIENT (WITH DRY AIR
OVER NORTH CENTRAL MISSISSIPPI AND MOISTURE ALONG AND WEST OF THE
MISSISSIPPI RIVER). STORMS SHOULD WEAKEN AS THEY MOVE EASTWARD AWAY
FROM THE MID LEVEL MOISTURE WEST OF THE RIVER. CONVECTION IS ALSO
DEVELOPING IN MADISON COUNTY IN CENTRAL MISSISSIPPI. WILL KEEP
ISOLATED TO WIDELY SCATTERED POPS IN THE FORECAST FOR ALL
ZONES...WITH HIGHEST POPS CENTRAL AND NORTH CLOSEST TO THE SURFACE
FRONTAL BOUNDARY. THE LAPS CAPES AND LIS SHOW THE GREATEST
INSTABILITY OVER CENTRAL MISSISSIPPI. WILL WORD A FEW STORMS MAY BE
SEVERE FOR EARLY EVENING IN CENTRAL AND EAST CENTRAL ZONES.

FOR PRECIPITATION BEYOND THIS EVENING...WILL KEEP ISOLATED POPS IN
FORECAST IN CENTRAL AND SOUTH SINCE DRY AIR WILL BE SLOW TO SINK
SOUTHWARD INTO SOUTHERN SECTIONS. THEN...EXPECT DRY CONDITIONS FOR
WEDNESDAY.

FOR TEMPERATURES...SHOULD SEE SOME UPPER 60S FOR LOWS IN NORTHERN
SECTIONS THE NEXT SEVERAL NIGHTS. WITH PLENTIFUL SUNSHINE EXPECTED
THROUGH WEDNESDAY...EXPECT MAXIMUM TEMPERATURES IN THE 90 TO 95
DEGREE RANGE. WILL GENERALLY FORECAST AN AVERAGE OF THE NGM AND AVN
GUIDANCE NUMBERS. DONT EXPECT TEMPERATURES QUITE AS COOL AS
FORECAST IN PREVIOUS ZONE PACKAGE.

EXTENDED FORECAST...AN UPPER LEVEL RIDGE SETTLING OVER THE REGION
SHOULD HELP TO MINIMIZE CHANCES OF AFTERNOON CONVECTION THROUGH
FRIDAY OR SATURDAY. THE TROPICAL STORM...CHANTAL...IS FORECAST TO
MOVE INTO NORTHERN MEXICO BY THURSDAY SO SHOULD NOT IMPACT OUR
WEATHER HERE. WILL STAY CONSISTENT WITH PREVIOUS ZONE PACKAGE ON
EXTENDED BRINGING CHANCE OF AFTERNOON STORMS IN BY SATURDAY OR
SUNDAY.

JAN 69/94/71/95/72 22--
MEI 67/93/67/94/69 2100

.JAN...
MS...NONE.
LA...NONE.
AR...NONE.
15

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>066-072>074-
211200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE JACKSON MS
245 PM CDT MON AUG 20 2001

...THUNDERSTORMS...
SCATTERED THUNDERSTORMS WILL DEVELOP OVER CENTRAL MISSISSIPPI...
SOUTHEAST ARKANSAS AND NORTHEAST LOUISIANA THROUGH EARLY TONIGHT.
ISOLATED STORMS MAY BECOME SEVERE WITH DIME SIZE HAIL OR WIND UP TO
60 MILES AN HOUR OVER PORTIONS OF CENTRAL AND EAST MISSISSIPPI...
MAINLY EAST OF AN ACKERMAN TO JACKSON TO QUITMAN LINE.

A FRONT THAT REMAINED NEARLY STATIONARY FROM GREENVILLE TO DEKALB
WILL SINK SLOWLY SOUTHWARD INTO EAST CENTRAL MISSISSIPPI THIS
EVENING. THIS FEATURE WILL FOCUS CONVECTIVE DEVELOPMENT IN ITS
VICINITY. AFTERNOON HEATING WILL ALSO PROVIDE LIFT TO THE MOIST
AND UNSTABLE AIR MASS TO THE SOUTH OF THE FRONT. A CLUSTER OF
STRONG TO SEVERE THUNDERSTORMS THAT CROSSED THE UPPER DELTA THIS
MORNING HAS STABILIZED THE AIRMASS IN THOSE AREAS.

ELSEWHERE...ISOLATED THUNDERSTORMS SHOULD NOT BECOME SEVERE OVER
MOST OF SOUTH MISSISSIPPI AND AREAS WEST OF INTERSTATE 55. ALL
THUNDERSTORMS SHOULD WEAKEN A COUPLE OF HOURS AFTER SUNSET.

ACTIVATION OF EMERGENCY MANAGEMENT PERSONNEL...STORM SPOTTERS AND
HAM RADIO OPERATORS SHOULD NOT BE NECESSARY THROUGH TONIGHT.

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