Slow moving thunderstorms developed over southern Missouri, dumping up to 6 inches of rain in a short amount of time. This 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 LSX wrote it up.
Slow moving thunderstorms developed over southern Missouri, dumping up to 6 inches of rain in a short amount of time. This 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 St. Louis, MO wrote its last area forecast discussion before the first event at Aug 18, 9:10 PM CST, 50 minutes earlier.
AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE ST LOUIS MO 1010 PM CDT TUE AUG 18 2009 .UPDATE... /1005 PM CDT TUE AUG 18 2009/ EASTWARD MOVING MCV AND WEAK 850MB MOISTURE ADVECTION/CONVERGENCE HAS INITIATED SCT SHRA/TSRA ACROSS CWA THIS EVENING. ONE PERSISTENT AREA OF BACK-BUILDING CONVECTION ACROSS REYNOLDS...IRON AND MADISON COUNTIES IN MISSOURI HAS PRODUCED VERY HEAVY RAINFALL...WITH RADAR ESTIMATES OVER 6 INCHES. FLASH FLOOD WARNINGS REMAIN IN EFFECT FOR THIS AREA...AND POINTS DOWNSTREAM ON LOCAL RIVERS. GUIDANCE SLOWLY SHIFTS THE THETA-E GRADIENT NORTH OVERNIGHT...SO EXPECT SCT CONVECTION TO SLOWLY ADVANCE NORTHEAST. CVKING && .DISCUSSION... /344 PM CDT TUE AUG 18 2009/ 20Z SFC DATA SHOWS STATIONARY FRONT EXTENDING FROM NCNTRL AR NEWD THRU SERN MO AND SRN IL AND SRN IN. FOR THE TIME BEING...THIS HAS SCOURED OUT SOME OF THE VERY MOIST AIR AND SHUNTED IT FURTHER S AND E FROM THE FA...BUT THIS WILL BE ONLY TEMPORARILY. THIS FRONTAL BOUNDARY IS EXPECTED TO ADVANCE NWD AS A WRMFNT LATER TONIGHT AND ON WEDNESDAY WITH THE MAIN CDFNT COMING THRU ON THURSDAY. WITH A RETURN OF THE VERY MOIST ATMOSPHERE THRU THE COLUMN IN THE NEAR FUTURE...IT WILL NOT TAKE MUCH TO KICK OFF ADDITIONAL PCPN. MCV FROM MORNING CONVECTION IN KS HAS STEADILY MOVED NEWD THRU CNTRL MO THIS AFTN AND WILL BE THE SOURCE FOR ISOLD EARLY EVENING TSRA BEFORE IT EXITS AND THE SUN GOES DOWN. AFTER THAT...SLOWLY RETURNING FRONTAL BOUNDARY WILL PROVIDE WEAK LIFT...AND BY LATE TONIGHT LOOK FOR THE FIRST OF SEVERAL INCURSIONS OF DEEP LIFT TO AFFECT OUR FA...WITH THIS ONE COMING FROM THE W. SO HAVE KEPT POPS RATHER LOW THRU MUCH OF THE NIGHT UNTIL LATE...WHERE THEY HAVE BEEN INCREASED TO OUR W. DEEP LIFT CONTINUES PRIMARILY OVER THE NWRN HALF OF THE FA ON WEDNESDAY...NW OF KSTL...AND SHOULD RESULT IN MCS TRACKING THRU MAINLY DURING THE MORNING HOURS. GIVEN THE AMOUNT OF RAIN PARTS OF THIS AREA HAS RECEIVED IN THE PAST COUPLE OF DAYS...THIS MAY BE A CANDIDATE FOR AN FFA ON WEDNESDAY DEPENDING ON HOW EXACTLY THIS SYSTEM DEVELOPS. BEYOND THIS...THINGS GET MORE MUDDLED...AS IT WILL DEPEND PARTIALLY ON HOW QUICKLY THE WEDNESDAY SYSTEM EXITS...BUT MOST MODELS ARE POINTING AT A RETURN OF DEEP LIFT BY LATE WEDNESDAY EVENING IN A VERY MOIST ATMOSPHERE WHICH SHOULD RESULT IN A RETURN OF WIDESPREAD PCPN. HAVE ADDED IN LOCALLY HEAVY RAINFALL POSSIBLE OVER THE NWRN HALF OF THE FA AS PWATS PEAK HERE SYNOPTICALLY COMBINED WITH NEWLY ADVANCING BUT SLOW MOVING FRONT AND A NOCTURNAL EVENT. THIS EVENT WILL CONTINUE THRU THURSDAY AS THE CDFNT FINALLY PUSHES THRU. MOS TEMPS LOOK REASONABLE...ESPECIALLY FAVORING COOLER NUMBERS IN AREAS THAT SHOULD RECEIVE A FAIRLY STEADY OR SEVERAL PERIODS OF PCPN. FOR THE EXTENDED PERIOD (FRIDAY NIGHT - TUESDAY)...MODELS IN REASONABLE AGREEMENT ON THIS PERIOD BEGINNING WITH DEEP TROF OVER THE ERN CONUS WITH HIGHLY AMPLIFIED FLOW OVER THE CNTRL CONUS. THE TROF WILL SLIDE AWAY WITH TIME AS WE HEAD THRU THE WEEKEND AND INTO EARLY NEXT WEEK AS A RIDGE BUILDS IN. THIS SHOULD SIGNAL A PERIOD OF GENERALLY DRY WX WITH INITIALLY COOL TEMPS REBOUNDING TOWARDS SEASONABLE VALUES. AT THE SFC...HI PRES WILL DOMINATE. THERE IS SOME DISAGREEMENT ON THE TIMING OF A CDFNT THAT MAY OR MAY NOT COME DOWN ON TUESDAY...AND FOR THIS REASON AND BECAUSE IT IS A WEEK AWAY HAVE LEFT THE ENTIRE PERIOD DRY FOR NOW. TES && .AVIATION... /631 PM CDT TUE AUG 18 2009/ FOR THE 00Z TAFS...SCT -SHRA ACROSS CENTRAL MO WILL MAINLY AFFECT COU EARLY THIS EVENING BEFORE DISSIPATING. NEXT CONCERN IS OVERNIGHT FOG CHANCES. WIDESPREAD CLD COVER SHOULD WORK AGAINST A REPEAT OF THE LOW CIGS/VSBYS THAT OCCURRED LAST NIGHT. HOWEVER...GIVEN AFTN RAINFALL...FOG IS LIKELY OVERNIGHT AT ANY LOCATIONS THAT CLEAR OUT. WILL MONITOR CLOUD TRENDS OVER THE NEXT FEW HOURS AND REEXAMINE FOG CONCERN FOR NEXT SET OF TAFS. ATTN THEN TURNS TO PRECIP EXPECTED ON WED AFTN. WARM FRONT WILL BEGIN MOVING NORTH TONIGHT...PROVIDING A FOCUS FOR SHOWERS AND THUNDERSTORMS ON WED AFTN. INTRODUCED VCSH/VCTS MENTION AT ALL SITES BEGINNING 14-18Z. EXPECT TO FURTHER REFINE THIS TIMING FOR NEXT ISSUANCE BASED ON LATEST GUIDANCE. KANOFSKY && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && WFO LSX
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE ST LOUIS MO 334 PM CDT TUE AUG 18 2009 ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027- 034>036-041-042-047>052-059>065-072>075-084-085-099-191200- GREENE IL-MACOUPIN IL-MONTGOMERY IL-BOND IL-FAYETTE IL-CLINTON IL- MARION IL-WASHINGTON IL-RANDOLPH IL-ADAMS IL-BROWN IL-PIKE IL- CALHOUN IL-JERSEY IL-MADISON IL-ST. CLAIR IL-MONROE IL-KNOX-LEWIS- SHELBY-MARION-MONROE-RALLS-PIKE-BOONE-AUDRAIN-MONITEAU-COLE-OSAGE- CALLAWAY-MONTGOMERY-LINCOLN-GASCONADE-WARREN-ST. CHARLES-FRANKLIN- ST. LOUIS-ST. LOUIS CITY-JEFFERSON-CRAWFORD-WASHINGTON- ST. FRANCOIS-STE. GENEVIEVE-IRON-MADISON-REYNOLDS- 334 PM CDT TUE AUG 18 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN AND CENTRAL MISSOURI AS WELL AS WEST CENTRAL AND SOUTHWEST ILLINOIS. .DAY ONE...TONIGHT THERE IS A SLIGHT CHANCE FOR THUNDERSTORMS. NO WIDESPREAD OR ORGANIZED SEVERE WEATHER IS EXPECTED. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY THE THREAT FOR THUNDERSTORMS WILL CONTINUE UNTIL THURSDAY EVENING. A FEW OF THE STORMS DURING THIS PERIOD COULD BE SEVERE...WITH THE PRIMARY THREATS BEING LARGE HAIL AND DAMAGING WIND GUSTS. SOME OF THE STORMS COULD ALSO PRODUCE LOCALLY HEAVY RAINFALL... ESPECIALLY ON WEDNESDAY NIGHT. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED TONIGHT. && FOR A GRAPHICAL VERSION OF THIS INFORMATION SEE OUR WEBPAGE AT (LOWERCASE)... HTTP://WWW.WEATHER.GOV/LSX/?N=HWO1 TES
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE ST LOUIS MO 709 PM CDT TUE AUG 18 2009 MOZ084-085-190045- IRON MO-MADISON MO- 709 PM CDT TUE AUG 18 2009 ...SIGNIFICANT WEATHER ADVISORY FOR IRON AND NORTHWESTERN MADISON COUNTIES UNTIL 745 PM CDT... AT 708 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM NEAR GLOVER...OR 7 MILES SOUTH OF IRONTON... MOVING NORTHEAST AT 10 MPH. HAIL UP TO THE SIZE OF PENNIES AND WIND GUSTS UP TO 50 MPH ARE EXPECTED WITH THIS STORM...ALONG WITH HEAVY RAIN AND FREQUENT DANGEROUS LIGHTNING. LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE... IRONTON... ARCADIA... PILOT KNOB... ROSELLE... THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO AND TV STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS...FOR ADDITIONAL INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE. CVKING
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE ST LOUIS MO 757 PM CDT TUE AUG 18 2009 MOZ074-190145- ST. FRANCOIS MO- 757 PM CDT TUE AUG 18 2009 ...SIGNIFICANT WEATHER ADVISORY FOR ST. FRANCOIS COUNTY UNTIL 845 PM CDT... AT 756 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM NEAR IRON MOUNTAIN...OR 6 MILES NORTHEAST OF IRONTON...MOVING NORTHEAST AT 15 MPH. HAIL UP TO THE SIZE OF PENNIES AND WIND GUSTS UP TO 50 MPH ARE EXPECTED WITH THIS STORM...ALONG WITH HEAVY RAIN AND FREQUENT DANGEROUS LIGHTNING. LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE... FARMINGTON... DOE RUN... LEADINGTON... CVKING
The St Louis radar (KLSX), 137 km away, was scanning. The volume nearest the first event began at 04:01 UTC.
1 flash flood. Local standard time, as filed.
Up to 6 inches of rain fell in a short amount of time causing flash flooding. Two feet of flowing water covered Highway U east of Lesterville.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Missouri in 2009Every state in 2009This day in weather historyWarnings in Missouri, 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: 188811.