Severe Thunderstorm Warning 618, NWS Jackson, MS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
252 PM CDT WED JUL 30 2003

MAIN FORECAST CHALLENGE THIS PACKAGE:
RAIN CHANCES THROUGH THE ENTIRE FORECAST PACKAGE

A RATHER PREDICTABLE WEATHER PATTERN CONTINUES ACROSS THE FORECAST
AREA THIS AFTERNOON.  SUBJECTIVE ANALYSIS EARLY THIS AFTERNOON HAS
THE NOW STATIONARY FRONT FROM ABOUT SPRINGFIELD MISSOURI TO
CHATTANOOGA TENNESSEE.  AS EXPECTED...AN MCS DEVELOPED LATE LAST
NIGHT AND MOVED ACROSS THE MID-SOUTH OVERNIGHT.  WITH SEVERAL
SHORTWAVES CONTINUING TO MOVE ACROSS THE FORECAST AREA...I EXPECT
MORE OF THE SAME AGAIN TONIGHT.  IN FACT...RADAR SHOWS WHAT COULD BE
THE BEGINNINGS OF TONIGHTS COMPLEX JUST NORTHWEST OF THE ARKLATEX.

AS THE UPPER-LEVEL LOW PINWHEELS INTO THE GREAT LAKES REGION DURING
THE END OF THE WEEK...THE FRONT SHOULD MOVE A LITTLE FURTHER INTO
THE FORECAST AREA AND GRADUALLY WEAKEN.  ANOTHER FRONTAL SYSTEM IS
FORECAST TO GET CRANKED UP OVER THE CENTRAL AND NORTHERN PLAINS AND
MOVE INTO THE MID- AND LOWER MISSISSIPPI VALLEY BY SATURDAY.  WITH
SHORTWAVES CONTINUING TO ROTATE THROUGH THE LONGER WAVE TROUGH...
THIS SPELLS MORE OF THE SAME FOR THE SHORT TERM...WITH THE FOCUS FOR
CONVECTIVE ACTIVITY SHIFTING A LITTLE FURTHER SOUTH.  RELATIVELY
SPEAKING...FRIDAY COULD BE THE DRIEST DAY IN THE SHORT TERM...AS 850
MB THETA-E VALUES DROP TO ALMOST 330K OVER OUR NORTHERN COUNTIES.  I
PLAN ON LEAVING THE STATUS QUO GOING OVER OUR SOUTHERN
COUNTIES/PARISHES...BUT REDUCE THE RAIN CHANCES OVER OUR NORTHERN
COUNTIES A LITTLE.

REGARDING THE RISK OF SEVERE WEATHER...THE JET STRUCTURE IS SOMEWHAT
OUT OF PHASE WITH THE REST OF THE SYSTEM.  COMBINED WITH A RATHER
WEAK MID-LEVEL FLOW...THE RISK FOR WIDESPREAD SEVERE WEATHER IS
LOW.  HOWEVER...I CANNOT RULE OUT A FEW PULSE-TYPE STORMS THROUGH
THURSDAY.  LATE THIS WEEKEND BEARS WATCHING THOUGH...AS AN 80 KNOT
JET STREAK AT 200 MB DIVES SOUTHEAST INTO THE FORECAST AREA.  THE
SHEAR MAY BE A LITTLE BETTER ABOUT THIS TIME AS WELL.

UNFORTUNATELY...IT DOESNT LOOK LIKE THERELL BE A WHOLE LOTTA
CHANGE IN THE OVERALL WEATHER PATTERN FROM SUNDAY THROUGH
WEDNESDAY.  THE VARIOUS LONG RANGER MODELS...INCLUDING THE GFS...
CANADIAN...ECMWF...NOT TO MENTION THE ENSEMBLES...ALL MAKE IT VERY
HARD NOT TO LEAN TOWARD AT LEAST CLIMATOLOGICAL TEMPERATURES AND
RAIN CHANCES.  A FRONT IS EXPECTED TO REMAIN VERY NEAR THE FORECAST
AREA THROUGH WEDNESDAY... AS SEVERAL SHORTWAVES DIVE DOWN AND ENTER
THE BASE OF THE LONGWAVE TROUGH.  AMPLE BOUNDARY LAYER MOISTURE AND
VARIOUS OUTFLOW BOUNDARIES SHOULD ALLOW SOME SHOWERS AND
THUNDERSTORMS TO BE SEEN EACH DAY.  THE DIFFICULTY WILL COME IN
TRYING TO PINPOINT (AT LEAST THIS FAR OUT) EXACTLY WHEN AND WHERE
THEY WILL FIRE.  LIKE I SAID BEFORE...ILL HEAD TOWARD CLIMATOLOGY
WITH CHANCE WORDING FOR SHOWERS AND STORMS THROUGH THE EXTENDED.  I
MAY BUMP UP OVERNIGHT LOWS A TAD...BUT HIGHS SHOULD BE JUST ABOUT
NORMAL.

ISC GRIDS HAVE BEEN SENT.  PRELIMINARY NUMBERS ARE LISTED BELOW.
FIRST PERIOD RAIN CHANCES ARE SUBJECT TO CHANGE BASED ON THE LATEST
RADAR IMAGES.

FCSTID =   10
JAN   73  89  73  92 /  50  40  40  20
MEI   73  89  72  92 /  50  50  40  20

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

BUTTS

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>066-072>074-
310922-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE JACKSON MS
422 AM CDT WED JUL 30 2003

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

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

...THUNDERSTORMS...
SCATTERED STRONG THUNDERSTORMS ARE EXPECTED TODAY ACROSS PORTIONS
OF SOUTHEASTERN ARKANSAS...NORTHEASTERN LOUISIANA AND CENTRAL
MISSISSIPPI. THE STRONGER STORMS WILL BE LOCATED MAINLY NORTH OF
INTERSTATE 20.	GUSTY WINDS TO 40 MPH...FREQUENT LIGHTENING AND
PERIODS OF HEAVY RAIN ARE EXPECTED WITH THE STRONGER STORMS. A
FEW OF THESE THUNDERSTORMS COULD BECOME SEVERE...PRODUCING WIND
GUSTS TO 60 MPH.

A FRONTAL BOUNDARY SAGGING SOUTHEAST THROUGH THE AREA TODAY WILL
SERVE AS A FOCUS FOR AFTERNOON THUNDERSTORM ACTIVITY. A WAVE
MOVING ALONG THE BOUNDARY ALONG WITH INSTABILITY ASSOCIATED WITH
DAILY HEATING WILL SERVE  FORCING MECHANISMS THAT WILL ENABLE THE
STRONG STORMS TO DEVELOP. THE PRESENCE OF MODERATE FLOW IN THE
LOWER AND MIDDLE LEVELS AND RELATIVELY FAVORABLE UPPER LEVEL JET
POSITIONING WILL ENABLE A FEW OF THE STORMS NORTH OF INTERSTATE
20 TO BRIEFLY BECOME SEVERE. HOWEVER...THE THUNDERSTORM
DEVELOPMENT COULD BE DELAYED UNTIL AFTERNOON IN THE NORTH DUE TO
THE PRESENCE OF A CIRRUS SHIELD IN THE MORNING.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY...

...DAYS TWO AND THREE...THURSDAY AND FRIDAY...
SCATTERED STRONG THUNDERSTORMS WITH ISOLATED SEVERE THUNDERSTORMS
WILL BE POSSIBLE ACROSS PORTIONS OF CENTRAL MISSISSIPPI AND EAST
CENTRAL LOUISIANA THURSDAY AFTERNOON...MAINLY SOUTH OF INTERSTATE
20. WIND GUSTS TO 40 MPH...FREQUENT LIGHTENING AND PERIODS OF
HEAVY RAIN ARE EXPECTED WITH THE PASSAGE OF THE STORMS. A FEW OF
THE THUNDERSTORMS COULD BECOME SEVERE.

AS THE FRONTAL BOUNDARY CONTINUES TO SLOWLY MOVE TO THE
SOUTHEAST...ANOTHER WAVE WILL PROPAGATE EASTWARD ALONG THE
BOUNDARY. LOWER AND MIDDLE LEVEL WIND FLOWS WILL AGAIN INCREASE
TO MODERATE SPEEDS. HOWEVER...UPPER LEVEL JET POSITIONING IS
EXPECTED TO BE SLIGHTLY OUT OF ALIGNMENT. SO ORGANIZED SEVERE
WEATHER ACTIVITY IS NOT EXPECTED...ONLY ISOLATED WITH THE MAIN
THREAT BEING WIND GUSTS.

...DAYS FOUR THROUGH SEVEN...SATURDAY THROUGH TUESDAY...
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...IS NOT ANTICIPATED THROUGH TONIGHT.

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