Severe Thunderstorm Warning 481, NWS Jackson, MS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON MS
320 AM CDT TUE JUN 26 2001

WILL BEGIN WITH A POSTANALYSIS OF YESTERDAY. ONE THUNDERSTORM
DEVELOPED NEAR KMEI...WHICH WAS FAIRLY WELL ANTICIPATED.
HOWEVER...WAS SURPRISED BY LACK OF THUNDERSTORM COVERAGE ON WESTERN
SIDE OF UPPER LOW. WATER VAPOR LOOP INDICATES THAT ENOUGH DRY AIR
WORKED AROUND THE WEST SIDE OF THE LOW TO EVEN OVERCOME THE
ADDITIONAL FORCING OF THE LEFT EXIT QUADRANT OF A JET STREAK WHICH
EVENTUALLY TRIGGERED THE ONE STORM. SURPRISE SHOWERS ALSO DEVELOPED
ALONG SOUTHERN BOUNDARY OF CWFA. IT APPEARS THAT THESE WERE
ASSOCIATED WITH A PRECIPITABLE WATER MAXIMUM AND A WEAK INSTABILITY
AXIS. 24 HOUR CHANGE CHARTS SHOW TEMPS AND DEWPOINTS BOTH HAVE
INCREASED IN THIS AREA...SO WILL INCLUDE ISOLATED SHOWERS THERE
AGAIN TODAY.

MODELS ARE AGAIN IN GOOD AGREEMENT IN THE LARGE SCALE...WITH THE
PREDICTABLE SCATTER IN THE DETAILS. PRECIPITABLE WATER INCREASES
WITH TIME...AND MID LEVEL COLD POOL CONTINUES MARCHING WESTWARD.
INSTABILITY WITH THIS COLD POOL WILL BE MAXIMIZED ALONG NORTHERN
BOUNDARY OF CWFA /NEAR HIGHWAY 82/. WILL RAISE GUIDANCE POPS IN THIS
AREA...CONTINUING PREVIOUS FORECAST TRENDS.

MAX TEMPERATURES BEHAVED WELL YESTERDAY...BUT LOWS HAVE PROVEN TO BE
A REAL HEADACHE. PLOT OF MORNING LOWS FROM METAR SITES AND COOP
OBSERVERS REVEAL A VERY DIFFICULT PATTERN TO FIGURE OUT. THE DELTA
EFFECT /WARM/ IS WELL REPRESENTED...AS IS THE NORTHEAST/NORTH
CENTRAL COLD ZONE...BUT THERE ARE SEVERAL OUTLIERS WHICH LIKELY ARE
DUE TO OVERNIGHT PATCHES OF CLOUD COVER. LOW LEVEL WIND DIRECTION
HAS ALSO PROVEN VERY DIFFICULT TO NAIL DOWN.

IN THE EXTENDED...SEE NO REASON TO DEPART FROM GOING FORECAST
TRENDS. PLENTY OF WARMTH AND MOISTURE AVAILABLE TO POP OFF AFTERNOON
CONVECTION...AND THE UPPER LOW WILL PROBABLY STILL BE SOMEWHERE
NEARBY AS WELL.

PRELIM NUMBERS...
JAN 89/66 88/66 2232
MEI 89/65 88/65 2232

.JAN...
MS...NONE.
LA...NONE.
AR...NONE.
06

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>066-072>074-
271200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE JACKSON MS
125 PM CDT TUE JUN 26 2001

...THUNDERSTORMS...
ISOLATED, SEVERE THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON
AND EVENING ACROSS PORTIONS OF NORTHEAST AND EAST CENTRAL
MISSISSIPPI...MAINLY ALONG AND NORTH OF A CARTHAGE TO
PHILADELPHIA TO DEKALB LINE AND EAST OF INTERSTATE 55.

THE ISOLATED SEVERE WEATHER THREAT IS EXPECTED TO BE FOR LARGE
HAIL AND STRAIGHT-LINE WINDS OF UP TO 60 MPH. FARTHER SOUTH AND
WEST, ONLY ISOLATED, NON-SEVERE SHOWERS AND THUNDERSTORMS ARE
EXPECTED.

ACTIVATION OF STORM SPOTTERS, EMERGENCY MANAGEMENT PERSONNEL, AND
HAM RADIO OPERATORS SHOULD NOT BE NECESSARY THROUGH TONIGHT.
HOWEVER, INTERESTS IN THE ISOLATED, SEVERE THREAT AREA SHOULD
STAY ABREAST OF WEATHER CONDITIONS LATE THIS AFTERNOON INTO THE
EARLY EVENING HOURS.

AN UPPER LEVEL LOW PRESSURE SYSTEM WILL CONTINUE MOVE WEST
TOWARDS THE MISSISSIPPI VALLEY REGION OF WESTERN TENNESSEE,
NORTHERN MISSISSIPPI, AND EASTERN ARKANSAS THROUGH TONIGHT. AS
THIS SYSTEM MOVES OVER THESE AREAS, LIFT AND COOLING IN THE UPPER
ATMOSPHERE WILL OCCUR ALONG WITH INCREASING LOW LEVEL MOISTURE
ALONG THE EAST SIDE OF THIS SYSTEM. SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO DEVELOP DURING THE AFTERNOON
HOURS...ESPECIALLY IN NORTHEAST AND EAST CENTRAL MISSISSIPPI. AN
ISOLATED STORM OR TWO MAY BECOME SEVERE WITH HAIL TO THE SIZE OF
DIMES AND DAMAGING WIND GUSTS TO 60 MPH. STORMS SHOULD BEGIN TO
DISSIPATE AND DIMINISH IN COVERAGE AFTER SUNSET...BUT A FEW
STORMS MAY PERSIST THROUGH MIDNIGHT.

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