A large thunderstorm complex moved through the southern half of Illinois with very heavy rainfall. Several reports of flash flooding were received.
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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.
A large thunderstorm complex moved through the southern half of Illinois with very heavy rainfall. Several reports of flash flooding were received.
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 Jul 15, 2:47 AM CST, 5 hours 43 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ST LOUIS MO 347 AM CDT WED JUL 15 2009 .DISCUSSION... /340 AM CDT WED JUL 15 2009/ MCS OVER SERN IA NWRN IL AND EXTREME NERN MO APRS TO BE STARTING TO ACCELERATE SEWD AS THE COLD POOL STRENGTHENS. THIS MCS SHOULD MOVE SEWD THRU THE NRN AND ERN PTNS OF THE CWA THIS MRNG BRINGING HVY RAINS. TSRA ACTIVITY SHOULD BE MORE SCT THIS MRNG ACRS THE SWRN PTN OF THE CWA. A LOT MORE UNCERTAINTY WITH COVERAGE OF CONVECTION THIS AFTN. CDFNT EXTDG FM MN SW THRU NWRN MO TO OK PNHDL ATTM SHOULD EXTD FM ERN WI SW THRU CNTRL MO TO NRN OK AT 18Z WED. OPERATIONAL MDLS HAVE CONVECTION MAINLY ALONG AND S OF I-70 THIS AFTN. THE NSSL 4 KM WRF DOES GENERATE A BKN LINE OF CONVECTION ALONG CDFNT IN CNTRL MO WHICH DROPS SEWD...BUT THE NCEP 4 KM WRF DOES NOT DVLP ANY CONVECTION...POSSIBLY BECAUSE THE ATMOSPHERE MAY BE TOO CAPPED FOR CONVECTION PLUS THE EFFECTIVE LOW LVL BNDRY DUE TO THE MRNG MCS WILL BE S OF THE CWA. WILL PUT AT LEAST CHC POPS OVER THE SRN OR SERN HALF OF THE CWA THIS AFTN. IF TSRA DVLP THIS AFTN THEY MAY BE SEVERE AS THE ATMOSPHERE WILL BE QUITE UNSTABLE. WILL FCST MAX TEMPS ABOVE PERSISTENCE TDA DESPITE CLOUD CVR AND PCPN EXPECTED DURING THE MRNG HRS. THE PCPN THREAT SHOULD SHIFT TO THE SRN PTN OF THE CWA TGT AS THE CDFNT EVENTUALLY DROPS SWD TO NRN AR BY 12Z THU. THE NAM MDL DEPICTS THE BETTER 850 MB DWPTS OVER SRN MO TGT. THE NAM...GFS AND ECMWF MDLS GENERATE QPF OVER THE SRN PTN OF THE CWA TGT...ALTHOUGH THE 4 KM WRF MDLS HAVE MOST OF THE PCPN S OF THE CWA. WILL CONT POPS OVER THE SRN AND SWRN PTN OF THE CWA ON THU AS SHRTWVS CONT TO MOVE THRU THE AREA AND MDLS DEPICT SOME UPR LVL DIVERGENCE OVER THE AREA WITH ULJ STREAKS MOVG THRU THE GRT LKS REGION. THERE WILL BE A CHANCE OF SHRA/TSRA OVER MOST OF THE CWA ON THU NGT AS ANOTHER CDFNT DROPS SEWD THRU THE AREA. UNSEASONABLY COOL AIR WITH LOW HUMIDITIES WILL BE FILTERING SEWD INTO THE AREA ON FRI WITH COOLER MAX TEMPS EXPECTED ON FRI. THIS COOL PATTERN WILL CONT THRU THE WKND WITH A STG MID-UPR LVL LOW OVER THE GRT LKS REGION AND N-NWLY MID-UPR LVL FLOW OVER THE AREA. A RELATIVELY STG SFC RDG WILL BUILD SEWD THRU THE AREA ON SAT. GKS && .AVIATION... /1153 PM CDT TUE JUL 14 2009/ FOR THE 06Z TAFS... PRECIP/TSTM CHANCES MAIN CONCERN WITH THIS PACKAGE. A WARM FRONT REMAINS DRAPED ACROSS MO. EARLIER SHRA/TSTM HAVE FADED WHILE ADDITIONAL SHRA/TSTM HAVE DEVELOPED OVER EASTERN KS AND SOUTHERN IA IN RESPONSE TO STRENGTHENING LLJ. AN MCS SHOULD DEVELOP ACROSS NORTHERN MO/SOUTHERN IA OVERNIGHT AND MOVE EAST. HAVE INTRODUCED TSRA AT ALL TAF SITES. THE MCS SHOULD PUSH AN OUTFLOW BOUNDARY THROUGH THE AREA IN ADVANCE OF A COLD FRONT. WINDS WILL BE WESTERLY TOMORROW BEHIND THE OUTFLOW BOUNDARY/COLD FRONT. CLOUDS WILL THIN DURING THE MORNING WITH DIURNAL CU LATER IN THE DAY. WINDS BECOME LIGHT/VRB OVERNIGHT WITH CENTER OF HIGH PASSING OVERHEAD. MILLER && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && WFO LSX
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE ST LOUIS MO 500 AM CDT WED JUL 15 2009 ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027- 034>036-041-042-047>052-059>065-072>075-084-085-099-161000- 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- 500 AM CDT WED JUL 15 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN AND CENTRAL MISSOURI AS WELL AS WEST CENTRAL AND SOUTHWEST ILLINOIS. .DAY ONE...TODAY AND TONIGHT THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS TODAY AND TONIGHT ACROSS MAINLY CENTRAL AND SOUTHEAST MISSOURI AS WELL AS SOUTHWEST ILLINOIS. THUNDERSTORMS ARE EXPECTED ALONG AND JUST AHEAD OF A COLD FRONT WHICH WILL BE MOVING SOUTHWARD THROUGH THE AREA. A FEW STORMS MAY BE CAPABLE OF PRODUCING DAMAGING WINDS AND LARGE HAIL ALONG WITH VERY HEAVY RAINFALL AND FREQUENT LIGHTNING. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY THE CHANCE FOR THUNDERSTORMS WILL CONTINUE THURSDAY AND THURSDAY NIGHT ESPECIALLY ACROSS CENTRAL AND SOUTHEAST MISSOURI AS WELL AS SOUTHWEST ILLINOIS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED TODAY AND TONIGHT. SPOTTERS ARE ENCOURAGED TO REPORT ANY SEVERE WEATHER TO THE NATIONAL WEATHER SERVICE. && FOR A GRAPHICAL VERSION OF THIS INFORMATION SEE OUR WEBPAGE AT (LOWERCASE)... HTTP://WWW.WEATHER.GOV/LSX/?N=HWO1 GKS
The St Louis radar (KLSX), 71 km away, was scanning. The volume nearest the first event began at 14:28 UTC.
1 flash flood. Local standard time, as filed.
Up to 4 inches of rain fell in a short amount of time causing flash flooding. One mile south of Medora, water was flowing over Illinois Route 111. Also, in Staunton several roads in town were flooded due to the heavy rain.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Illinois in 2009Every state in 2009This day in weather historyWarnings in Illinois, July 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: 188338.