Severe Thunderstorm Warning 273, NWS Jackson, MS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
1255 PM CDT THU JUL 15 2004

&&

.SHORT TERM...SEVERE THUNDERSTORM WATCH CURRENTLY IN EFFECT...BUT
EXPECT FOCUS TO SHIFT SOUTH TONIGHT. NEXT CONCERN WILL BE FRIDAY
AFTERNOON THROUGH SATURDAY AS THE FRONTAL BOUNDARY PUSHES SOUTHWARD
OVER THE AREA. EXPECT CONVECTION TO DEVELOP FRIDAY AFTERNOON ALONG
AND SOUTH OF THE FRONTAL BOUNDARY AS THE ATMOSPHERE WILL BE
EXTREMELY UNSTABLE WITH CAPES NEAR 5000 J/KG. GFS INDICATES A
THETA-E RIDGE EXTENDING ACROSS NORTH CENTRAL MISSISSIPPI...THIS
ALONG WITH A 500MB LOW CENTERED OVER TN AND A 500MB VORT MAX MOVING
THROUGH THE SAME AREA...EXPECT THE FOCUS OF ANY SEVERE ACTIVITY TO
BE OVER THE NORTHERN COUNTIES...HOWEVER WILL NEED TO WATCH HOW THE
MESOSCALE ENVIRONMENT EVOLVES. ANOTHER IMPULSE OF ENERGY WILL MOVE
THROUGH THE AREA FRIDAY NIGHT INTO SATURDAY MORNING ALONG THE
BOUNDARY. EXPECT THE FOCUS OF THUNDERSTORM ACTIVITY TO SHIFT A
LITTLE FURTHER SOUTH WITH THE BOUNDARY AS IT EXTENDS ACROSS CENTRAL
MS. WITH AMPLE CAPE AND SHEAR AVAILABLE SEVERE THUNDERSTORMS WILL
AGAIN BE POSSIBLE. SEE HWO FOR DETAILS.

&&

.LONG TERM...COLD FRONT MOVING THROUGH THE AREA ON SATURDAY WILL
GIVE WAY TO DRYING CONDITIONS AND NORTHERLY FLOW ON MONDAY. THERE
WILL BE SOME RESIDUAL SHOWERS SUNDAY MORNING OVER THE SOUTHERN
COUNTIES AS THE BOUNDARY HANGS UP IN THE SOUTH. EXPECT CLEARING
SKIES ON MONDAY INTO TUESDAY WITH LOW U/L RH VALUES. U/L RIDGE
BEGINS TO BUILD IN ON TUESDAY...WITH A RETURN TO MORE SEASONAL
SOUTHERLY FLOW WITH DIURNAL THUNDERSTORMS ON WEDNESDAY AND THURSDAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
JACKSON       73  92  71  91 /  40  40  30  40
MERIDIAN      72  91  70  90 /  40  40  50  40

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...HEAT ADVISORY MUCH OF WEST AND SOUTH TIL 00Z THURSDAY.
LA...NONE.
AR...NONE.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE JACKSON MS
548 AM CDT THU JUL 15 2004

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>066-072>074-
161048-
ADAMS-ASHLEY-ATTALA-BOLIVAR-CARROLL-CATAHOULA-CHICOT-CHOCTAW-
CLAIBORNE-CLARKE-CLAY-CONCORDIA-COPIAH-COVINGTON-EAST CARROLL-
FORREST-FRANKLIN LA-FRANKLIN MS-GRENADA-HINDS-HOLMES-HUMPHREYS-
ISSAQUENA-JASPER-JEFFERSON-JEFFERSON DAVIS-JONES-KEMPER-LAMAR-
LAUDERDALE-LAWRENCE-LEAKE-LEFLORE-LINCOLN-LOWNDES-MADISON LA-
MADISON MS-MARION-MONTGOMERY-MOREHOUSE-NESHOBA-NEWTON-NOXUBEE-
OKTIBBEHA-RANKIN-RICHLAND-SCOTT-SHARKEY-SIMPSON-SMITH-SUNFLOWER-
TENSAS-WARREN-WASHINGTON-WEBSTER-WEST CARROLL-WINSTON-YAZOO-
548 AM CDT THU JUL 15 2004

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

.DAY ONE...TODAY AND TONIGHT...

...THUNDERSTORMS...
ISOLATED SEVERE THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON AND
EVENING OVER PORTIONS OF CENTRAL AND SOUTH MISSISSIPPI...MAINLY
TO THE EAST OF A NATCHEZ TO VICKSBURG TO BELZONI LINE.

A COLD FRONT HAS PUSHED INTO ARKANSAS AND NORTH MISSISSIPPI THIS
MORNING. THE FRONT WILL SLOW ITS SOUTHWARD PUSH AND EVENTUALLY
STALL TODAY OVER SOUTHERN ARKANSAS AND CENTRAL MISSISSIPPI. THE
AIR WILL BE VERY UNSTABLE SOUTH OF THE FRONT...AND ANY STORMS
THAT DEVELOP LATER TODAY COULD QUICKLY BECOME STRONG...AND
POSSIBLY SEVERE WITH LARGE HAIL AND WIND GUSTS OF 60 TO 70 MPH.

THE GREATEST UNCERTAINTY FOR TODAY CONCERNS THE AREAL COVERAGE OF
THUNDERSTORMS. OVER NORTHERN PORTIONS OF THE OUTLOOK
AREA...POSITIONING OF THE JET STREAM WILL NOT BE FAVORABLE FOR
STORMS TO DEVELOP...SO COVERAGE IS EXPECTED TO BE SCATTERED AT
BEST. FARTHER SOUTH...ESPECIALLY SOUTH OF INTERSTATE 20...UPPER
LEVEL CONDITIONS WILL BE MORE FAVORABLE FOR THUNDERSTORM
DEVELOPMENT...AND STORMS THAT DEVELOP ALONG THE COAST COULD
ENHANCE CONVERGENCE OVER SOUTH MISSISSIPPI LATE THIS AFTERNOON
AND EVENING.

SO OVERALL...THE GREATER RISK FOR ORGANIZED THUNDERSTORMS AND
SEVERE WEATHER APPEARS TO BE OVER SOUTH MISSISSIPPI.

...SEASONAL THREATS...
HEAT INDEX VALUES WILL RISE TO AROUND 105 OVER MUCH OF THE
OUTLOOK AREA BY THIS AFTERNOON...ESPECIALLY TO THE SOUTHWEST OF A
CLEVELAND...TO LEXINGTON...TO DEKALB LINE. PLEASE REFER TO THE
HEAT ADVISORY FOR MORE DETAILS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY...

...DAYS TWO AND THREE...FRIDAY AND SATURDAY...
A MORE FAVORABLE SET UP FOR SEVERE THUNDERSTORMS WILL EXIST
FRIDAY INTO SATURDAY. AN UNSEASONABLY STRONG UPPER LEVEL TROUGH
WILL COMBINE WITH VERY MOIST AND UNSTABLE AIR OVER THE REGION TO
SUPPORT THE PASSAGE OF ONE OR TWO CONVECTIVE COMPLEXES DURING
THIS PERIOD. DAMAGING WINDS AND LARGE HAIL WILL BE POSSIBLE WITH
SOME STORMS...AND AN ISOLATED TORNADO CANNOT BE RULED OUT.
TORRENTIAL RAINFALL AND FREQUENT LIGHTNING STRIKES CAN BE
EXPECTED WITH THE STRONGER STORMS.

...DAYS FOUR THROUGH SEVEN...SUNDAY THROUGH WEDNESDAY...
NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER CALL TO ACTION STATEMENT...
THE ACTIVATION OF STORM SPOTTERS...HAM RADIO OPERATORS... AND
EMERGENCY MANAGEMENT PERSONNEL IN SUPPORT OF SEVERE WEATHER
OPERATIONS...MAY BE NEEDED AT SOME POINT LATER TODAY...AND AGAIN
FRIDAY OR SATURDAY.

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