Flash Flood Warning 149, NWS Memphis, TN

000 
WGUS74 KMEG 111552
FFSMEG

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MEMPHIS TN
1052 AM CDT TUE AUG 11 2009

TNC023-039-071-077-109-113-111602-
/O.EXP.KMEG.FF.W.0149.000000T0000Z-090811T1600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
DECATUR TN-HENDERSON TN-MADISON TN-CHESTER TN-HARDIN TN-MCNAIRY TN-
1052 AM CDT TUE AUG 11 2009

...THE FLASH FLOOD WARNING WILL EXPIRE AT 1100 AM CDT FOR
NORTHEASTERN MCNAIRY...NORTHERN HARDIN...CHESTER...SOUTHEASTERN
MADISON...SOUTHERN HENDERSON AND DECATUR COUNTIES...THE HEAVY 
RAINFALL WHICH PROMPTED THE WARNING HAS DIMINISHED OVER THE WARNED 
AREA. THUS THE FLASH FLOOD WARNING HAS BEEN ALLOWED TO EXPIRE

THIS WARNING INCLUDES THE FOLLOWING LOW WATER CROSSINGS IN DECATUR
COUNTY BIBLE HILL ROAD AT SHIPMAN CREEK...BIBLE HILL ROAD IN
PARSONS...CONCORD ROAD AT LESTER CREEK...FAIRGROUND ROAD...LARGE ROAD
AT RUSSIAN CREEK...LARGO ROAD 4...NORTHWOOD STREET IN PARSONS AND OLD
LEXINGTON ROAD AT BEAR CREEK.

.STAY TUNED TO THIS BROADCAST FOR THE LATEST UPDATES AND INFORMATION.
TO REPORT SEVERE WEATHER ONLY...CALL 1 800 4 3 2 0 8 7 5.

LAT...LON 3548 8798 3546 8804 3543 8803 3542 8798
      3538 8799 3539 8802 3536 8802 3532 8879
      3562 8879 3571 8802 3567 8801 3561 8802
      3555 8797 3550 8796

$$

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEMPHIS TN
656 AM CDT TUE AUG 11 2009

.UPDATE...
UPDATED TO ADD 12Z AVIATION DISCUSSION.

&&
.PREV DISCUSSION... /ISSUED 336 AM CDT TUE AUG 11 2009/

DISCUSSION...

SHORT-TERM (TODAY THROUGH THURSDAY NIGHT)...

A SERIES OF MESOSCALE CONVECTIVE SYSTEMS (MCS) HAVE DEVELOPED
ALONG A CONVECTIVE OUTFLOW BOUNDARY THAT IS CURRENTLY STRETCHED
FROM OKLAHOMA SOUTHEASTWARD ACROSS SOUTHERN ARKANSAS. HIGH CLOUDS
FROM THE CONVECTIVE TOPS HAVE MOVED ACROSS THE MID SOUTH THIS
MORNING PROVIDING PARTLY CLOUDY SKIES IN MOST AREAS. THESE
CONVECTIVE SYSTEMS SHOULD REMAIN WELL SOUTHWEST OF OUR AREA THIS
MORNING.

PRIMARY MID LEVEL SHORTWAVE CURRENTLY OVER THE CENTRAL PLAINS INTO
THE UPPER MISSISSIPPI VALLEY WILL DIG SOUTHEAST INTO THE TENNESSEE
VALLEY DURING THE DAY. THIS MID LEVEL SHORTWAVE COMBINED WITH THE
RIGHT ENTRANCE REGION OF AN 85KT UPPER LEVEL JET STREAK OVER THE
OHIO VALLEY WILL FOCUS INCREASED LARGE SCALE LIFT OVER THE MID
SOUTH LATER TODAY. THIS SYNOPTIC LIFT COMBINED WITH INCREASING
INSTABILITY FROM DAYTIME HEATING AND LOW LEVEL LIFT ALONG A
SOUTHEASTWARD MOVING COLD FRONT SHOULD SUPPORT LIKELY CHANCES FOR
SHOWERS AND THUNDERSTORMS. SBCAPES RANGING FROM 1500-3000J/KG...LI/S
BETWEEN -4C AND -6C...AND DEEP LAYER SHEAR BETWEEN 25 AND 35
KNOTS...SHOULD SUPPORT MULTICELLULAR STORM STRUCTURES SOME OF
WHICH MAY BE SEVERE. SPC HAS PLACED MUCH OF THE MID SOUTH UNDER A
SLIGHT RISK FOR SEVERE THUNDERSTORMS TODAY AND THIS SEEMS
REASONABLE CONSIDERING THE STRENGTH OF THE SHORTWAVE AND EXPECTED
MODERATE INSTABILITY. THE PRIMARY SEVERE WEATHER THREATS WILL BE
DAMAGING WINDS AND LARGE HAIL. PERIODS OF HEAVY RAIN AND LOCALIZED
FLASH FLOODING WILL ALSO BE POSSIBLE AS PRECIPITABLE WATER VALUES
REMAIN ABOVE 2 INCHES. LATEST HWO WILL CONTINUE TO HIGHLIGHT THE SEVERE
WEATHER POTENTIAL.

THE COLD FRONT WILL MOVE SOUTHEAST INTO NORTHERN MISSISSIPPI BY
LATER TONIGHT AND SOUTH OF THE FORECAST AREA BY WEDNESDAY
AFTERNOON. SHOWERS AND THUNDERSTORMS WILL CONTINUE IN THE VICINITY
OF THE FRONTAL BOUNDARY TONIGHT INTO WEDNESDAY MORNING.

HIGH PRESSURE WILL BUILD OVER THE AREA ON WEDNESDAY AFTERNOON AND
REMAIN IN PLACE THROUGH THE END OF THE WEEK. THIS WILL PROVIDE DRY
WEATHER AND NEAR SEASONABLE TEMPERATURES FOR THE END OF THIS WEEK.

JLH

LONG-TERM (FRIDAY THROUGH MONDAY)...

00Z ECMWF/GFS LONG RANGE MODELS CONTINUE TO INDICATE HIGH
PRESSURE BRINGING RAIN FREE WEATHER TO THE MID SOUTH FRIDAY. AS
SURFACE/UPPER LEVEL RIDGING MOVE EAST BY SATURDAY...LOW LEVEL
MOISTURE FROM THE GULF OF MEXICO WILL BRING CHANCES FOR SHOWERS
AND THUNDERSTORMS BACK TO THE AREA FOR THE REMAINDER OF THE
PERIOD...ESPECIALLY DURING THE AFTERNOON/EARLY EVENING HOURS.
TEMPERATURES THROUGH THE PERIOD ARE EXPECTED TO AVERAGE NEAR
NORMAL TO SLIGHTLY ABOVE NORMAL.

CJC

&&

.AVIATION...
12Z TAF CYCLE

CHALLENGING AVIATION FORECAST THIS MORNING AS ATMOSPHERE REMAINS VERY
MOIST AND UNSTABLE ACROSS TAF SITES AND SCATTERED
SHOWERS/THUNDERSTORMS HAVE DEVELOPED AS OF 12Z ACROSS PORTIONS OF
W TN AND N MS. ADDITIONAL SHOWERS AND THUNDERSTORMS ANTICIPATED
TO DEVELOP AND BECOME MORE NUMEROUS AS COLD FRONT/UPPER LEVEL
TROUGH MOVES THROUGH THE REGION LATE THIS AFTERNOON INTO TONIGHT.
AS A RESULT...HAVE GONE WITH PREVAILING VCTS AND TEMPOS FROM
17-19Z AT JBR...18-20Z AT MEM...19-21Z AT MKL...AND 20-22 AT TUP
WHEN CONVECTIVE ACTIVITY ASSOCIATED WITH COLD FRONT ARRIVES AT TAF
SITES.

CJC
&&

.PRELIMINARY POINT TEMPS/POPS...
MEM  90  72  90  70 /  60  40  10  10
MKL  89  70  88  64 /  60  40  10  10
JBR  88  68  88  65 /  60  30  10  10
TUP  91  72  91  67 /  60  60  20  10

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MEMPHIS TN
424 AM CDT TUE AUG 11 2009

ARZ008-009-017-018-026>028-035-036-048-049-058-MOZ113-115-
MSZ001>017-020>024-TNZ001>004-019>021-048>055-088>092-121130-
ALCORN-BENTON MS-CALHOUN-CARROLL-CHESTER-CHICKASAW-CLAY-COAHOMA-
CRAIGHEAD-CRITTENDEN-CROCKETT-CROSS-DESOTO-DECATUR-DUNKLIN-DYER-
FAYETTE-GIBSON-GREENE-HARDEMAN-HARDIN-HAYWOOD-HENDERSON-HENRY-
ITAWAMBA-LAFAYETTE-LAKE-LAUDERDALE-LAWRENCE-LEE AR-LEE MS-MADISON-
MARSHALL-MCNAIRY-MISSISSIPPI-MONROE-OBION-PANOLA-PEMISCOT-
PHILLIPS-POINSETT-PONTOTOC-PRENTISS-QUITMAN-RANDOLPH-SHELBY-
ST. FRANCIS-TALLAHATCHIE-TATE-TIPPAH-TIPTON-TISHOMINGO-TUNICA-
UNION-WEAKLEY-YALOBUSHA-
424 AM CDT TUE AUG 11 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST ARKANSAS...
THE MISSOURI BOOTHEEL...NORTH MISSISSIPPI...AND WEST TENNESSEE.

.DAY ONE...TODAY AND TONIGHT

THERE IS A SLIGHT RISK FOR SEVERE WEATHER OVER THE MID SOUTH
TODAY. AN UPPER LEVEL DISTURBANCE COMBINED WITH A SURFACE COLD
FRONT AND INCREASING INSTABILITY WILL PROVIDE LIKELY CHANCES FOR
SHOWERS AND THUNDERSTORMS. THESE STORMS MAY BECOME SEVERE WITH
DAMAGING WINDS AND LARGE HAIL THE PRIMARY THREATS. HEAVY RAINFALL
AND LOCALIZED FLOODING MAY ALSO ACCOMPANY THE STRONGEST STORMS.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

THE ACTIVATION OF STORM SPOTTERS...EMERGENCY MANAGEMENT...AND LAW
ENFORCEMENT MAY BE NEEDED TODAY.

JLH