Severe Thunderstorm Warning 51, NWS Jackson, MS

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE JACKSON MS
945 PM CST FRI FEB 27 2009

...SEVERE WEATHER AND HEAVY RAIN RISK TO CONTINUE INTO TONIGHT...

.DISCUSSION...

UPDATE: NO MAJOR ADJUSTMENTS WERE NECESSARY TO THE OVERNIGHT
FORECAST GRIDS AND PRODUCTS. THE E-W FRONTAL BOUNDARY HAS SAGGED A
LITTLE FARTHER SOUTH THAN ANTICIPATED RESULTING IN MORE DISJOINTED
SEVERE WEATHER/FLOODING SETUP...BUT THE SCENARIO IS STILL PLAYING
OUT AS FORECAST WITH REDEVELOPMENT OF SHOWERS/TSTMS TAKING PLACE
ALONG THE HWY 82 CORRIDOR AS NEXT UPPER LEVEL WAVE ASSOC WITH THE
EXIT REGION OF UPPER JET HELPS TRIGGER CONVECTION. WILL THUS
CONTINUE TO THE FLASH FLOOD WATCH OVER NC MS. IN THE LOWER
LEVELS...THE FRONTAL BOUNDARY IS BUCKLING IN RESPONSE AND THIS WILL
HELP COLDER AIR SPREAD ACROSS THE ENTIRE AREA AS WE GO INTO SATURDAY
MORNING.

ML CAPE AHEAD OF THE FRONT IS FORECAST TO LESSEN AND FALL BELOW 500
J/KG...BUT 0-1 KM SHEAR VALUES WILL REMAIN QUITE STRONG AT ~30KT AND
SUPPORTIVE OF CONTINUED SEVERE WEATHER POTENTIAL THROUGH THE
REMAINDER OF THE NIGHT. THE BIGGEST CONCERN IS THE STRENGTH OF THE
MID LEVEL CAPPING INVERSION OVER SRN PORTIONS OF THE AREA AND JUST
HOW MUCH FORCING WILL BE REQUIRED TO REMOVED THE CAP AND ALLOW FOR
DEEP CONVECTION. THE 00Z LIX SOUNDING INDICATED A STRONG CAP IN
PLACE ~750 MB AND IF IT IS ANY INDICATION OF THE ENVIRONMENT ALONG
THE HWY 84 CORRIDOR...WOULD NOT EXPECT TO SEE MUCH TSTM ACTIVITY
THERE AS STRONGER FORCING IS EXPECTED TO REMAIN NORTH OF I-20.

EXPECT THE TORNADO POTENTIAL WILL DECREASE TOWARD DAWN AS LOW LEVEL
FLOW VEERS...BUT STEEP MID LEVEL LAPSE RATES WILL CONTINUE TO
SUPPORT LARGE HAIL AND AND SFC-BASED STORMS THAT CAN DEVELOP AHEAD
OF THE COLD FRONT WILL BE CAPABLE OF DAMAGING WINDS. LOOK FOR THE
SEVERE WEATHER RISK TO DROP OFF QUICKLY BEHIND THE ADVANCING COLD
FRONT SATURDAY MORNING. /EC/

PREVIOUS DISCUSSION...

SATURDAY THROUGH NEXT FRIDAY...SHOWERS AND STORMS SHOULD BE PULLING
AWAY FROM EASTERN MISSISSIPPI SHORTLY AFTER DAYBREAK...BUT THERE
STILL MAY BE AN OPPORTUNITY FOR A FEW POTENT STORMS NEAR THE I-59
CORRIDOR AFTER DAYBREAK AND BEFORE 10 AM. INSTABILITY WILL NOT BE
HIGH...BUT WIND SHEAR WILL BE SUFFICIENT FOR ORGANIZED CELLS...SO
THIS POTENTIAL WILL HAVE TO BE MONITORED.

THE REST OF THE SATURDAY SHOULD FEATURE A LOT OF CLOUDS...GUSTY
NORTHWEST WINDS...AND PERHAPS SOME LINGERING LIGHT RAIN SHOWERS.
WINDS (AT LEAST IN UPPER DELTA SECTIONS) MAY BE STRONG ENOUGH TO
NECESSITATE A LAKE WIND ADVISORY...BUT I WILL LET SUBSEQUENT SHIFT
HANDLE THAT. TEMPERATURES MAY TEND TO DROP DURING THE DAY IN A FEW
PLACES WITH VERY COOL HIGHS IN THE UPPER 40S TO MID 50S.

THE REALLY INTERESTING WEATHER WILL COME IN SATURDAY NIGHT INTO
EARLY SUNDAY AS THE PREVIOUSLY MENTIONED UPPER LOW COMES PLOWING
SOUTH IN THE LOWER MS VALLEY. MODELS HAVE REACHED A GOOD CONSENSUS
THAT THE SYSTEM WILL DIG STRONGLY DOWN INTO OUR REGION...BUT WILL
NOT MAKE IT TO THE GULF COAST. THIS PUTS LOCATIONS ROUGHLY ALONG AND
NORTH OF A CLEVELAND TO DE KALB LINE IN MISSISSIPPI IN THE ZONE OF
ACCUMULATING SNOW POTENTIAL. SOME LIGHT SNOW (PERHAPS MIXED WITH
RAIN AT TIMES) MAY FALL SOUTH OF THIS LINE...BUT ACCUMULATIONS ARE
NOT ANTICIPATED. AT THIS POINT IT SEEMS POSSIBLE THAT ACCUMULATIONS
UP TO TWO INCHES MAY BE POSSIBLE UP IN THE GOLDEN
TRIANGLE...SATURDAY NIGHT THROUGH SUNDAY MORNING...WITH MAYBE AN
INCH TO A DUSTING ELSEWHERE IN THE DEFINED AREA. WITH SUCH A SMALL
AREA OF THE CWA SHOWING THE BEST POTENTIAL (AND STILL SOME
UNCERTAINTY WITH THE UPPER LOW TRACK) I WILL HOLD OFF ON ISSUING ANY
SORT OF WATCHES OR ADVISORIES. HOWEVER...SUBSEQUENT SHIFTS WILL HAVE
TO STRONGLY CONSIDER THIS IN AT LEAST THE FAR NORTHEAST PORTION OF
THE ARKLAMISS IF MODELS REMAIN CONSISTENT IN THEIR SOLUTIONS.

THE REST OF THE FORECAST WAS ESSENTIALLY UNCHANGED AND I HAVE POSTED
THE RELEVANT PORTIONS OF THE PREVIOUS LONG RANGE FORECAST DISCUSSION
BELOW. /BB/

BEGINNING SUNDAY THE AREA WILL SEE A PROLONGED PERIOD OF DRY WEATHER
THROUGH AT LEAST AROUND THURSDAY OR SO. COOL SURFACE HIGH PRESSURE
IS EXPECTED TO SET UP OVER THE ARKLAMISS REGION THROUGH THE
BEGINNING OF THE WORK WEEK WITH WEAK CAA PERSISTING THROUGH THIS
TIME.  THIS WILL BE REFLECTED IN TEMPERATURES WITH LOWS THROUGH THE
FIRST PART OF THE WORK WEEK AROUND OR A FEW DEGREES BELOW FREEZING.
HIGH TEMPERATURES SUNDAY WILL REMAIN IN THE MIDDLE 50S OR
LOWER...WITH SLIGHTLY WARMER TEMPERATURES ON MONDAY.

BY WEDNESDAY THOUGH THE REMAINDER OF THE WORK WEEK THE AREA SHOULD
SEE A DECENT WARM UP.  THERE WILL BE A DECENT UPPER RIDGE OVER THE
REGION.  AND THE SURFACE HIGH IS EXPECTED TO SHIFT TO THE EAST OF
THE FORECAST AREA. THIS WILL BRING RETURN FLOW TO THE ARKLAMISS
REGION TO GIVE MUCH WARMER TEMPERATURES BY THE END OF THE WORK WEEK
WITH HIGHS IN THE 60S AND INTO THE MIDDLE 70S EXPECTED. HAVE WENT
AHEAD AND RAISED TEMPERATURES BY A COUPLE DEGREES FOR MOST SITES FOR
HIGHS WEDNESDAY AND THURSDAY...BRINGING TEMPERATURES CLOSER TO
ENSEMBLE GUI VALUES. MODELS ARE IN A BIT OF DISAGREEMENT AS TO WHEN
RAIN WILL RETURN TO THE ARKLAMISS REGION...BUT AT THIS TIME IT LOOKS
AS IF THE AREA SHOULD REMAIN DRY THROUGH AT LEAST FRIDAY...POSSIBLY
LONGER INTO THE WEEKEND./14/

&&

.AVIATION...THE MAIN FOCUS OF THE FORECAST IS TRYING TO TIME THE
CONVECTION AND FRONTAL PASSAGE. THIS WILL CONTINUE TO BE TOUGH AS
FRONTAL BOUNDARY HAS WANTED TO MOVE LITTLE OVER THE PAST SEVERAL
HOURS. THE WORST CONDITIONS WILL PERSIST ALONG AND NORTH OF THE
HIGHWAY 82 CORRIDOR. THIS INCLUDES GWO AND GTR...WITH A LESS EXTENT
AT GLH. MULTIPLE STORMS AND STORM CLUSTERS ARE ANTICIPATED FROM LATE
THIS EVENING INTO THE OVERNIGHT HOURS. AS THE FRONT MOVES THROUGH
THE REGION...EXPECT IT WILL CONGEAL INTO A SQUALL LINE AND MOVE
THROUGH THE REGION BETWEEN MIDNIGHT AND SUNRISE. GENERALLY VFR
CONDITIONS WILL PREVAIL AT SITES ALONG AND SOUTH OF INTERSTATE 20
WITH SOME MVFR CONDITIONS WITH ANY SHOWER ACTIVITY. AS THE FRONT AND
ASSOCIATED SQUALL LINE MOVE THROUGH...MVFR TO IFR CONDITIONS WILL
OCCUR AT TAF SITES.

MVFR TO IFR CEILINGS WILL REMAIN UNTIL SUNDAY WITH SOME LIFR
CONDITIONS POSSIBLE AS WELL. THERE WILL ALSO BE SOME LIGHT SNOW
DEVELOP OVER THE NE HALF OF THE AREA SAT NIGHT. ALL CONDITIONS
SHOULD IMPROVE BY SUN AFTERNOON. /28/

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...FLASH FLOOD WATCH UNTIL 3 AM CST SATURDAY FOR
MSZ018-019-025>039. LA...NONE.
AR...NONE.

&&

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE JACKSON MS
342 PM CST FRI FEB 27 2009

MSZ018-019-025>039-282145-
BOLIVAR-SUNFLOWER-LEFLORE-GRENADA-CARROLL-MONTGOMERY-WEBSTER-CLAY-
LOWNDES-CHOCTAW-OKTIBBEHA-WASHINGTON-HUMPHREYS-HOLMES-ATTALA-
WINSTON-NOXUBEE-
342 PM CST FRI FEB 27 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH MISSISSIPPI.

.DAY ONE...TONIGHT AND SATURDAY

SCATTERED TO NUMEROUS SEVERE THUNDERSTORMS WILL CONTINUE TO BE
POSSIBLE THIS EVENING AND INTO TONIGHT. SUPERCELL THUNDERSTORMS AND
OTHER STORM CLUSTERS WILL BE POSSIBLE IN THIS REGION THROUGH THE
EVENING WHICH WILL BE CAPABLE OF PRODUCING LARGE HAIL...BETWEEN
QUARTER AND GOLF BALL SIZE. OTHER RISKS WILL COME FROM DAMAGING WINDS
AND POSSIBLE TORNADOES...ESPECIALLY FROM ANY SUPERCELL STORMS THAT
OCCUR.

THROUGH THE OVERNIGHT HOURS...AS THE COLD FRONT BEGINS TO PUSH
SOUTHEAST THROUGH THE AREA...THE ACTIVITY WILL CONGEAL INTO A SQUALL
LINE IN WHICH ALL MODES OF SEVERE WEATHER WILL CONTINUE TO BE
POSSIBLE ACROSS THE OUTLOOK AREA.

IN ADDITION TO THE SEVERE WEATHER POTENTIAL...DUE TO THE REPETITIVE
NATURE OF SHOWERS AND STORMS ACROSS THE SAME AREA...SEVERAL
LOCATIONS ACROSS THE HIGHWAY 82 CORRIDOR HAVE BEEN EXPERIENCING
LOCALIZED FLOODING THIS AFTERNOON. UNTIL THE FRONT BEGINS TO MAKE ITS
PUSH FURTHER TO THE SOUTH LATER TONIGHT...LOCALIZED FLOODING WILL
CONTINUE TO BE A CONCERN ACROSS THE AREA. AREAS ALONG AND NORTH OF A
LINE FROM GREENVILLE TO MACON LOOK TO HAVE THE GREATEST POTENTIAL TO
SEE AN ADDITIONAL 3 TO 5 INCHES OF RAIN THROUGH TONIGHT.

.DAYS TWO THROUGH SEVEN...SATURDAY NIGHT THROUGH THURSDAY

LIGHT SNOW WILL BE POSSIBLE SATURDAY EVENING INTO EARLY SUNDAY MORNING
FOR AREAS MAINLY ALONG AND EAST OF A CLEVELAND TO DEKALB LINE.
AT THIS TIME...SNOWFALL ACCUMULATIONS SHOULD REMAIN AT OR BELOW AN
INCH. AS RESULT...A WINTER WEATHER WATCH OR ADVISORY MAY BE NEEDED
FOR PORTIONS OF THIS AREA FOR SATURDAY NIGHT. PLEASE CONTINUE TO
CHECK BACK FOR LATER FORECASTS CONCERNING THIS POSSIBLE WINTER
WEATHER EVENT.

.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 TONIGHT INTO EARLY SATURDAY MORNING.
OTHERWISE...ACTIVATION IS NOT EXPECTED THROUGH NEXT THURSDAY.

ARZ074-075-LAZ007>009-015-016-MSZ040>052-282145-
ASHLEY-CHICOT-MOREHOUSE-WEST CARROLL-EAST CARROLL-RICHLAND-
MADISON LA-ISSAQUENA-SHARKEY-YAZOO-MADISON MS-LEAKE-NESHOBA-
KEMPER-WARREN-HINDS-RANKIN-SCOTT-NEWTON-LAUDERDALE-
342 PM CST FRI FEB 27 2009

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

.DAY ONE...TONIGHT AND SATURDAY

ISOLATED TO SCATTERED SEVERE THUNDERSTORMS WILL BE POSSIBLE ACROSS
THE AREA THIS EVENING AND INTO TONIGHT. ISOLATED SUPERCELL
THUNDERSTORMS WILL ALSO BE POSSIBLE IN THIS REGION THROUGH THE
EVENING. LARGE HAIL...STRONG DAMAGING WINDS...AND TORNADOS WILL ALL
BE POSSIBLE FROM ANY SUPERCELL STORMS THAT OCCUR.

THROUGH THE OVERNIGHT HOURS...AS THE COLD FRONT BEGINS TO PUSH
SOUTHEAST THROUGH THE AREA...THE ACTIVITY WILL CONGEAL INTO A SQUALL
LINE IN WHICH ALL MODES OF SEVERE WEATHER WILL CONTINUE TO BE
POSSIBLE ACROSS THE OUTLOOK AREA.

.DAYS TWO THROUGH SEVEN...SATURDAY NIGHT THROUGH THURSDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.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 TONIGHT INTO EARLY SATURDAY MORNING.
OTHERWISE...ACTIVATION IS NOT EXPECTED THROUGH NEXT THURSDAY.

LAZ023>026-MSZ053>066-072>074-282145-
FRANKLIN LA-CATAHOULA-TENSAS-CONCORDIA-CLAIBORNE-COPIAH-SIMPSON-
SMITH-JASPER-CLARKE-JEFFERSON-ADAMS-FRANKLIN MS-LINCOLN-LAWRENCE-
JEFFERSON DAVIS-COVINGTON-JONES-MARION-LAMAR-FORREST-
342 PM CST FRI FEB 27 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST LOUISIANA
AND SOUTH MISSISSIPPI.

.DAY ONE...TONIGHT AND SATURDAY

AN ISOLATED SEVERE THUNDERSTORM MAY BE POSSIBLE SOUTH OF INTERSTATE 20
TONIGHT AND INTO EARLY SATURDAY MORNING. IF ONE CAN DEVELOP...IT
WILL QUICKLY BECOME SEVERE AND BE CAPABLE OF PRODUCING LARGE
HAIL AND STRONG DAMAGING WINDS. HOWEVER...A TORNADO OR TWO CANNOT BE
RULED OUT. THE BEST TIME FRAME FOR ANY SEVERE STORMS TO DEVELOP
ACROSS THIS AREA WILL BE AFTER MIDNIGHT AS THE COLD FRONT PUSHES
THROUGH EAST CENTRAL LOUISIANA AND SOUTHERN MISSISSIPPI.

.DAYS TWO THROUGH SEVEN...SATURDAY NIGHT THROUGH THURSDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.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 LATE TONIGHT INTO EARLY SATURDAY MORNING.
OTHERWISE...ACTIVATION IS NOT EXPECTED THROUGH NEXT THURSDAY.

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

19

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE JACKSON MS
956 PM CST FRI FEB 27 2009

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0937 PM     HAIL             2 SE COLUMBUS AFB       33.61N 88.43W
02/27/2009  E0.75 INCH       LOWNDES            MS   COUNTY OFFICIAL

&&

CME

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PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE JACKSON MS
314 AM CST SAT FEB 28 2009

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0313 AM     FLASH FLOOD      COLUMBUS                33.51N 88.40W
02/28/2009                   LOWNDES            MS   LAW ENFORCEMENT

            SEVERAL ROADS IN COLUMBUS AND IN THE COUNTY HAVE WATER
            COVERING THEM. ON SOME ROADS THE ASPHALT IS BROKEN DUE TO
            WATER.

&&

JCULIN