Severe Thunderstorm Warning 656, NWS Jackson, MS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
300 AM CDT WED AUG 6 2003

TODAYS MAIN FORECAST PROBLEM REVOLVES AROUND THE CHANCE OF
PRECIPITATION AND THE MAX TEMPERATURES. THE OTHER MAIN FORECAST
QUANDARY IS WHAT HOW FAR SOUTH AND HOW FAST THE FRONTAL BOUNDARY
WILL MOVE SOUTH OVER THE CWFA.

DEVELOPING THUNDERSTORM COMPLEX CURRENTLY MOVING OVER THE NORTHWEST
CWFA. A LOT DEPENDS ON THE PROGRESSION OF THIS SYSTEM...SUCH AS MAX
TEMPS UNDER THE CLOUD COVER...A MESOSCALE BOUNDARY LEFT OVER FROM
THE SYSTEM...HOW FAR SOUTH THIS FEATURE WILL MAKE IT. CURRENT
THINKING IS TO HAVE THE HIGHEST POPS ALONG THE PROJECTED PATH OF THE
COMPLEX FOR THE MORNING HOURS. NONE OF THE MODELS ARE REALLY
HANDLING THIS FEATURE VERY WELL...THE ETA HAS IT TOO FAR NORTH...AND
THE AVN DOESNT HANDLE IT AT ALL. THE REAL QUESTION IS: WILL
CONVECTION RE-FIRE BEHIND THE COMPLEX LATER ON DURING THE DAY. SOME
STABILIZATION SHOULD OCCUR BEHIND THE COMPLEX LATER THIS MORNING
...HOWEVER IF THE CLOUD COVER BREAKS...THE ATMOSPHERE IS MOIST AND
UNSTABLE ENOUGH TO RECOVER FOR AFTERNOON CONVECTION. WILL HAVE THE
HIGHEST POPS IN THE DELTA THIS MORNING...BUT DECREASE THEM TO LOW
END SCATTERED THIS AFTERNOON. HARDER TO PINPOINT THE POPS FOR THE
REMAINDER OF THE AFTERNOON...SINCE CONVECTION WILL BE FIRING ALONG
MESOSCALE FEATURES...BUT WILL KEEP IN THE 30 TO 40 PERCENT RANGE.

IN ADDITION TO THE PROBLEMATIC THUNDERSTORM COMPLEX...A FRONTAL
BOUNDARY WITH A SURFACE WAVE SHOULD BEGIN APPROACHING THE CWFA LATE
TODAY INTO THE OVERNIGHT HOURS. MODELS DO SHOW PRECIP LINGERING INTO
THE OVERNIGHT HOURS ALONG AND AHEAD OF THE BOUNDARY. WILL CONTINUE
OVERNIGHT POPS. THIS BOUNDARY WILL STILL BE HANGING AROUND THROUGH
THE DAY THURSDAY...MOVING PRETTY SLOWLY SOUTH. BOTH MODELS HAVE THE
BOUNDARY MOVING TO THE COAST BY LATE THURSDAY...WITH HIGH PRESSURE
MOVING IN BEHIND THE BOUNDARY BY FRIDAY. A DRIER AIRMASS WILL SETTLE
OVER THE CWFA. COOLER MINIMUM TEMPS BEHIND THE BOUNDARY ALSO.

NO MAJOR CHANGES WERE MADE TO THE EXTENDED FORECAST. THE CURRENT
FORECAST LOOKS TO BE ON TRACK.

PRELIM NUMBERS...
JAN TB 090/073 090/069 092 32533
    BBBBB 071/093 070/092 070/090 072/091 072 21110222233
MEI BB 090/072 090/068 092 32433
    BBBBB 068/093 067/092 068/091 070/091 070 21110222233

32/LISTEMAA

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>066-072>074-
071956-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE JACKSON MS
256 PM CDT WED AUG 06 2003

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

.DAY ONE...TONIGHT AND THURSDAY...

...THUNDERSTORMS...
SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE OVER THE
AREA THROUGH WEDNESDAY NIGHT AS A SLOW MOVING COLD FRONT MOVES
INTO THE LOWER MISSISSIPPI VALLEY. SOME OF THESE THUNDERSTORMS
COULD BE SEVERE...ESPECIALLY ACROSS PORTIONS OF NORTHEAST
LOUISIANA...SOUTHEAST ARKANSAS AND NORTH CENTRAL
MISSISSIPPI...ALONG AND NORTH OF A LINE FROM BASTROP...TO YAZOO
CITY TO WEST POINT. THE MAIN RISK FROM ANY SEVERE THUNDERSTORMS
WILL BE FROM HAIL AND DAMAGING WINDS. SCATTERED THUNDERSTORMS ARE
ANTICIPATED AGAIN THURSDAY ALONG AND SOUTH OF INTERSTATE
TWENTY...WHILE ONLY ISOLATED THUNDERSTORMS ARE EXPECT IN NORTHERN
PORTIONS OF THE AREA. AT THIS TIME SEVERE THUNDERSTORMS ARE NOT
EXPECTED DURING THE DAY TOMORROW.

THE COMBINATION OF STRONG WINDS ALOFT...A SOUTHWARD MOVING
FRONTAL BOUNDARY AND STRONG ATMOSPHERIC INSTABILITY AT THE
SURFACE IS EXPECTED TO TRIGGER STRONG TO SEVERE THUNDERSTORMS
ACROSS NORTHWEST MISSISSIPPI AND SOUTHEAST ARKANSAS BY EARLY
WEDNESDAY EVENING. OTHER STORMS ELSEWHERE IN THE AREA COULD ALSO
BRIEFLY REACH SEVERE LIMITS. STORMS IN NORTHWEST MISSISSIPPI AND
SOUTHEAST ARKANSAS SHOULD ORGANIZE INTO A BROKEN LIKE OF
CONVECTION WHICH WILL PUSH SOUTH AND EAST THROUGH A GOOD PORTION
OF THE REGION DURING THE NIGHT. STORMS WILL GRADUALLY WEAKEN
DURING THE LATE EVENING HOURS...BUT THE POTENTIAL FOR AT LEAST
ISOLATED SEVERE WEATHER SHOULD LAST SEVERAL HOURS AFTER SUNSET.

...FLOODING...
HEAVY RAIN AND LOCALIZED FLOODING WILL BE POSSIBLE THROUGH
WEDNESDAY EVENING...GENERALLY IN AREAS BOTH ALONG AND EAST OF
INTERSTATE FIFTY-FIFTY AND ALONG AND NORTH INTERSTATE TWENTY.

SCATTERED THUNDERSTORMS WEDNESDAY AFTERNOON ACROSS THESE AREAS OF
MISSISSIPPI ARE EXPECTED TO REPEATEDLY AFFECT THE SAME LOCATIONS
AS THEY TRACK TO THE EAST AND SOUTHEAST. THIS SCENARIO WILL
RESULT IN LOCALIZED RAINFALL ACCUMULATIONS OF 1 TO 3 INCHES.
PONDING ON ROADWAYS AND FLOODING OF POOR DRAINAGE AREAS WILL BE
POSSIBLE.

.DAYS TWO THROUGH SEVEN...THURSDAY NIGHT 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 THIS EVENING.

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