Severe Thunderstorm Warning 317, NWS Jackson, MS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
245 PM CDT WED JUL 17 2002

NOT MUCH CHANGE IN THE FORECAST FROM PREVIOUS ISSUANCES...AS MODELS
GENERALLY AGREE ON THE EVOLUTION OF THE UPPER RIDGE THROUGH THU AND
THEN THE UPPER TROUGH/SHEAR AXIS THROUGH MON.

UPPER RIDGE SETTLING NICELY OVER THE REGION AS I WRITE. THIS FEATURE
WILL CONTINUE TO DOMINATE LOCAL WEATHER UNTIL LATE THU. SFC TEMPS
ARE TRYING THEIR HARDEST TO REACH THE MID 90S. SFC MOISTURE IS
WORKING AGAINST THIS PROCESS...BUT TEMPS SHOULD TOP OUT IN THE 92-95
DEGREE RANGE. EXPECT MUCH OF THE SAME FOR THU...WITH MAX TEMPS A
DEGREE OR TWO HIGHER. MAIN CONCERN WILL BE WITH THE HEAT LIKE
TODAY...EXPECT HEAT INDICES TO RANGE BETWEEN 100-105. JUST A LITTLE
BELOW CRITERIA TO MENTION IN ZONES...BUT IT IS STILL SUFFICIENT
ENOUGH TO MENTION. WILL ONLY INCLUDE ISOLATED POPS NW...DUE TO THE
PROXIMITY OF THE UPPER SHEAR AXIS. THIS WILL INCLUDE TONIGHT AND THU.

THINGS CHANGE FOR FRI. UPPER SHEAR AXIS GETS PUSHED BACK TO THE SE
AS NW FLOW ENERGY MOVES CLOSER. BEST LOW LEVEL MOISTURE MOVES INTO
THE NORTHERN 1/3 OF THE FORECAST AREA. WE WILL HAVE TO WATCH FOR THE
POSSIBILITY OF SEVERE ON FRI AFTN. COLD POOL ALOFT MOVES IN WITH
ASSOCIATED SHEAR AXIS. INCREASING LOW LEVEL MOISTURE FROM THE SW AND
WARM 850 TEMPS WILL GIVE WAY TO FAIRLY STEEP LAPSE RATES. STILL 60
HRS OUT...BUT WILL WATCH. UPPER SHEAR AXIS WILL REMAIN OVER THE AREA
THROUGH MON...AND SHOULD PROVIDE FOR AT LEAST SCT POPS. OVERALL...
BEST RAIN CHANCES WILL BE ACROSS THE NORTHERN 1/3 TO NORTHERN 1/2.
TUE/WED ARE A LITTLE THINGS ARE NOT AS CLEAR CUT...GUIDANCE HAS BEEN
FLIP FLOPPING WITH THE PATTERN AND CONFIDENCE IS A LITTLE LOW ON
WHAT/WHERE THE SHEAR AXIS WILL BE LOCATED. WILL LEAVE SCT CHANCES
FOR NOW AND WAIT FOR SOME CONSISTENCY AND FOLLOW THE TREND.

JAN 70/94/71/94/73  0003
MEI 70/95/70/95/72  0003

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

36

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>066-072>074-
181200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE JACKSON MS
1255 PM CDT WED JUL 17 2002

...THUNDERSTORMS...
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE THROUGH 9 PM ACROSS
EXTREME SOUTHEAST ARKANSAS...EASTERN LOUISIANA...AND NORTHERN
MISSISSIPPI.  THIS INCLUDES THE
HAMBURG...GRENADA...COLUMBUS...BASTROP...AND HARRISONBURG AREAS.
SEVERE WEATHER IS NOT EXPECTED THIS AFTERNOON OR EVENING.

A MOIST AND SOMEWHAT UNSTABLE AIRMASS REMAINS ACROSS NORTHERN
MISSISSIPPI...SOUTHEAST ARKANSAS...AND EASTERN LOUISIANA.  WITH
STRONG DAYTIME HEATING...ISOLATED TO SCATTERED THUNDERSTORMS ARE
EXPECTED TO DEVELOP AROUND MID AFTERNOON.  THE GREATEST COVERAGE
OF SHOWERS AND THUNDERSTORMS WILL BE WEST OF A LINE FROM
CLEVELAND MISSISSIPPI TO BASTROP LOUISIANA.

WHILE SEVERE WEATHER IS NOT EXPECTED...THE STRONGER STORMS MAY
PRODUCE WIND GUSTS UP TO 40 MILES AN HOUR AND FREQUENT LIGHTNING.
 LOCALLY HEAVY RAINFALL MAY ALSO BE SEEN.

FURTHER SOUTH AND EAST...INCLUDING THE
JACKSON...MERIDIAN...HATTIESBURG...AND NATCHEZ AREAS...A RIDGE OF
HIGH PRESSURE IN THE UPPER ATMOSPHERE HAS BROUGHT SLIGHTLY DRIER
AND MORE STABLE CONDITIONS TO THE REGION.  ACROSS THIS
REGION...THUNDERSTORMS ARE NOT EXPECTED.

THE ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT
PERSONNEL...IN SUPPORT OF SEVERE WEATHER OPERATIONS...WILL NOT BE
REQUIRED THROUGH TONIGHT.

...SEASONAL THREATS...
HEAT INDICES BETWEEN 100 AND 105 DEGREES CAN BE EXPECTED ACROSS
MUCH OF CENTRAL AND SOUTHERN MISSISSIPPI THIS
AFTERNOON...INCLUDING THE
JACKSON...MERIDIAN...HATTIESBURG...VICKSBURG...NATCHEZ...AND
COLUMBIA AREAS.
THE COMBINATION OF TEMPERATURES IN THE MIDDLE 90S AND RELATIVE
HUMIDITY VALUES NEAR 50 PERCENT WILL PRODUCE HEAT INDEX VALUES
APPROACHING 105 DEGREES THIS AFTERNOON.

PEOPLE WORKING OUTDOORS...AND IN AREAS OF LITTLE
VENTILATION...SHOULD DRINK PLENTY OF NON-ALCOHOLIC BEVERAGES AND
AVOID OVER-EXERTING THEMSELVES.

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