Remnants of a mesoscale convective system moved into North Mississippi during the afternoon on August 11, 2009. Some of thunderstorms produced heavy rain which caused flash flooding.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS MEG wrote it up.
Remnants of a mesoscale convective system moved into North Mississippi during the afternoon on August 11, 2009. Some of thunderstorms produced heavy rain which caused flash flooding.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Memphis, TN wrote its last area forecast discussion before the first event at Aug 11, 8:34 AM CST, 2 hours 56 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MEMPHIS TN 934 AM CDT TUE AUG 11 2009 .DISCUSSION... CLOUDS ARE INCREASING ACROSS THE FORECAST AREA THIS MORNING WITH TEMPERATURES IN THE MID 70S TO MID 80S. SHOWERS AND THUNDERSTORMS CAN BE FOUND MAINLY ON EITHER SIDE OF THE TENNESSEE/MISSISSIPPI BORDER. THUNDERSTORM ACTIVITY SHOULD INCREASE IN COVERAGE DURING THE AFTERNOON SO WILL LEAVE POPS ALONE. CURRENT FORECAST APPEARS TO BE IN GOOD SHAPE SO NO CHANGES ARE PLANNED AT THIS TIME. ARS && .PREV DISCUSSION... /ISSUED 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
The Columbus AFB radar (KGWX), 58 km away, was scanning. The volume nearest the first event began at 17:28 UTC.
1 flash flood. Local standard time, as filed.
Heavy rain produced flash flooding in Tupelo. Up to a foot of water covered several streets. A few vehicles were trapped in flood waters as well.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Mississippi in 2009Every state in 2009This day in weather historyWarnings in Mississippi, August 2009
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 195238.