Severe Thunderstorm Warning 281, NWS Jackson, MS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
330 PM CDT WED JUL 10 2002

FOR THE REMAINDER OF THE WEEK...CONCERNS WILL CENTER AROUND THE
IMPLICATIONS OF A STRONG SHORTWAVE TROUGH THAT IS EXPECTED TO DIG
SOUTHWARD THROUGH THE MIDWEST AND INTO THE LOWER MISSISSIPPI VALLEY
REGION BY FRIDAY. THE LATEST MODEL GUIDANCE INDICATES THE POTENTIAL
FOR A STRONG CONVECTIVE SYSTEM TO DEVELOP LATE FRIDAY BRINGING A
THREAT FOR SEVERE WEATHER TO THE FORECAST AREA.

A RATHER COMPLICATED SCENARIO APPEARS TO BE SHAPING UP THE NEXT FEW
DAYS. MODEL GUIDANCE IS IN GOOD AGREEMENT ON THE GENERAL PATTERN IN
HANDLING OF THE AFOREMENTIONED MIDWEST SHORTWAVE AND ALSO THE MID
LEVEL LOW CENTER CURRENTLY OVER THE EASTERN GULF. COMPLICATIONS
ARISE IN HOW THESE FEATURES INTERACT AND WHERE THE BEST HEIGHT FALLS
WILL OCCUR. CONVECTIVE CLUSTERS ARE CURRENTLY INITIATING ALONG A
SURFACE FRONT EXTENDING FROM THE CNTRL PLAINS THRU THE OH VALLEY.
THIS FRONTAL BOUNDARY SHOULD SAG SLOWLY SOUTHWARD AND EXPECT THAT
TODAYS CONVECTIVE SCENARIO WILL REPLAY A BIT FARTHER SOUTH ON
THURSDAY. JUST HOW FAR SOUTH IS THE IMPORTANT QUESTION OF COURSE.
GIVEN THE POSITION OF THE MID LEVEL RIDGE AXIS CURRENTLY IN PLACE
FROM SRN PLAINS EASTWARD INTO THE LOWER MS VALLEY REGION...EXPECT
THE BEST FRONTAL CONVERGENCE WILL REMAIN NORTH OF THE FORECAST AREA
AT LEAST EARLY THURSDAY. IN ADDITION...BELIEVE THAT COMPLEX
CURRENTLY ENTERING TN SHOULD DIMINISH THIS EVENING AS IT RACES AHEAD
OF THE FRONTAL SUPPORT. IN ANY CASE...LOOKS LIKE ENOUGH MOISTURE/
INSTABILITY AND INSOLATION WILL EXIST THURSDAY FOR TYPICAL
AFTN/EVENING CONVECTION...SIMILAR TO TODAY. WILL HIT PRECIP CHANCES
HARDEST OVER NRN COUNTIES BASED ON POSSIBILITY OF ORGANIZED FRONTAL
CONVECTION BY LATE IN THE DAY.

FOR FRIDAY INTO SATURDAY...BOTH ETA AND AVN INDICATE A SIGNIFICANT
BAND OF WESTERLIES...ASSOC WITH THE WELL DEFINED MID LEVEL TROF...
ENCROACHING UPON THE AREA. PRECIPITABLE WATER VALUES IN EXCESS OF 2
INCHES AND MODERATE SFC BASED INSTABILITY (3000-4000 J/KG CAPES) ARE
PROGGED TO BE IN PLACE AHEAD OF THE LOW LEVEL FRONT. THE EXPECTED
BAROCLINICITY AND STORM ORGANIZATION WITH THIS SORT OF ENVIRONMENT
IMPLIES A DISTINCT THREAT FOR SEVERE TSTM ACTIVITY...BUT WILL HOLD
OFF ON ANY SUCH MENTION FOR NOW WITH THE POSSIBLE EVENT STILL WELL
INTO THE LATTER FORECAST PERIODS. WILL CONTINUE CURRENT FORECAST
TREND OF HIGHER PRECIP CHANCES FOR FRIDAY INTO SATURDAY.

IN THE EXTENDED...12Z AVN LOOKS TO BE IN AGREEMENT ON MAINTAINING
MID LEVEL TROUGH AXIS FROM WRN OH VALLEY REGION SWWD THRU TX. THIS
WILL KEEP THE FORECAST AREA IN AN ACTIVE SUMMER WX REGIME THAT
SHOULD INCLUDE CONSIDERABLE AFTN/EVENING CONVECTIVE PRECIPITATION
AND TEMPS NEAR CLIMATOLOGY. WILL KEEP IN CONCERT WITH RECENT
FORECASTS OF DAILY PRECIP CHANCES THRU EXTENDED FORECAST.

PRELIM NUMBERS...
JAN 73/94/73/91/72 24355
MEI 72/93/72/92/72 24355

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

43

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>066-072>074-
111200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE JACKSON MS
118 PM CDT WED JUL 10 2002

...THUNDERSTORMS...
ISOLATED THUNDERSTORMS WILL BE POSSIBLE OVER MOST OF
MISSISSIPPI... SOUTHEAST ARKANSAS AND NORTHEAST LOUISIANA THROUGH
THE REMAINDER OF THIS AFTERNOON AND INTO THE EVENING HOURS.
THUNDERSTORMS WILL BE MORE NUMEROUS OVER PARTS OF NORTH AND WEST
MISSISSIPPI...AS WELL AS NORTHEAST LOUISIANA...MAINLY ALONG AND
NORTH OF A LINE FROM MACON...TO MORTON...TO BOGUE CHITTO. SEVERE
WEATHER IS NOT EXPECTED.

IN STRONGER STORMS....GUSTY WINDS UP TO 40 MPH ALONG...FREQUENT
LIGHTNING STRIKES...AND BRIEF HEAVY DOWNPOURS MAY OCCUR. WHILE
DIURNAL HEATING WILL HELP SPARK SHOWERS AND THUNDERSTORMS...THE
PRESENCE OF SEVERAL OUTFLOW BOUNDARIES FROM EARLIER
CONVECTION...ALONG WITH A NORTHWARD-MOVING SEA BREEZE
FRONT...WILL HELP TO FOCUS STORM DEVELOPMENT. THE SHOWERS AND
THUNDERSTORMS WILL END OVER MOST AREAS BY 10 PM.

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

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