A stationary frontal boundary served as the focusing mechanism for scattered thunderstorms during the late afternoon and early evening hours of July 12th. Most of the storms occurred along and southwest of a Springfield to Robinson line.
Every event with a place to put it. Tap one for its entry below.
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 ILX wrote it up.
A stationary frontal boundary served as the focusing mechanism for scattered thunderstorms during the late afternoon and early evening hours of July 12th. Most of the storms occurred along and southwest of a Springfield to Robinson line. Isolated wind damage was reported, as well as localized flash flooding across parts of southeast Illinois.
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 Lincoln, IL wrote its last area forecast discussion before the first event at Jul 12, 1:50 PM CST, 57 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LINCOLN IL 250 PM CDT TUE JUL 12 2011 .DISCUSSION... ISSUED 250 PM CDT TUE JUL 12 2011 ANOTHER HOT/HUMID DAY UNFOLDING ACROSS CENTRAL AND SOUTHEAST ILLINOIS TODAY...THOUGH THE PASSAGE OF A WEAK COLD FRONT HAS USHERED IN LESS OPPRESSIVE CONDITIONS THAN YESTERDAY ACROSS ALL BUT SOUTHEAST PORTIONS OF THE FORECAST AREA. MAIN FORECAST CONCERNS TODAY REVOLVE AROUND PRECIPITATION CHANCES UNTIL FRONT SINKS A LITTLE FARTHER SOUTH...AS WELL AS THE RETURN OF OPPRESSIVE HEAT FOR THE WEEKEND INTO NEXT WEEK. AS HAS BEEN THE CASE FOR LATELY...MODELS/ENSEMBLES IN GOOD AGREEMENT WITH RESPECT TO THE LARGE SCALE PATTERN OVER THE NEXT SEVERAL DAYS. HOWEVER...AS CAN BE EXPECTED...STRUGGLES PERSIST ON THE TIMING...COVERAGE...AND PLACEMENT OF THE SMALLER SCALE CONVECTIVE THREAT. THIS IS A LESSER CONCERN THAN IT HAS BEEN THE PAST FEW DAYS THOUGH AS OUR CURRENT FORECAST PERIOD SHOULD BE LARGELY DRY. SHORT TERM...TONIGHT THROUGH FRIDAY...WHILE THE FRONTAL BOUNDARY HAS SHIFTED SOUTH OF THE FORECAST AREA FOR THE MOST PART...THE DRIER AND MORE STABLE AIR LAGS BEHIND THE FRONT TO SOME DEGREE. THIS WILL ALLOW LOW SHOWER/STORM CHANCES TO LINGER ALONG/JUST NORTH OF THE FRONTAL BOUNDARY INTO WEDNESDAY. HOWEVER...THE AIRMASS WILL HAVE COOLED/DRIED SUFFICIENTLY BY WEDNESDAY TO LET THE EXCESSIVE HEAT WARNING IN SOUTHEAST ILLINOIS EXPIRE AS PLANNED AT 7 PM TONIGHT. MOSTLY QUIET WEATHER IS ANTICIPATED FOR LATER WEDNESDAY INTO FRIDAY WITH HIGH PRESSURE IN CONTROL AT THE SURFACE AND RIDGING IN THE VICINITY ALOFT. THAT BEING SAID...THERE ARE A COUPLE FEATURES TO KEEP AN EYE ON THAT WILL POSE AT LEAST A SLIGHT RISK OF SHOWER/STORMS TO THE FORECAST AREA. THE FIRST IS A SMALL CUTOFF LOW...CURRENTLY OVER OKLAHOMA...DRIFTING BENEATH THE MEAN RIDGE OVER THE CENTRAL UNITED STATES. THE SECOND IS A WAVE/MCS THAT WILL TOP THE THE MEAN RIDGE THURSDAY INTO FRIDAY. THE FIRST WAVE DOES NOT HAVE MUCH STEERING FLOW TO DIRECT WHERE IT WILL TRACK...THOUGH THE MODEL CONSENSUS GENERALLY HAS IT DRIFT EAST BEFORE IT TRACKS SOUTHEAST ALONG THE MISSISSIPPI RIVER ON THURSDAY. THE SECOND WAVE/POTENTIAL MCS IS PROGGED BY THE BULK OF THE MODELS TO STAY TO OUR NORTH WITH THE STRONGER WIND FIELDS AND LOWER CONVECTIVE INHIBITION. SO...WITH THIS THINKING IN MIND...HAVE GONE WITH NO MORE THAN SLIGHT CHANCES OF SHOWERS/STORMS ON THE WESTERN/NORTHERN FRINGES OF THE FORECAST AREA AS THESE FEATURES MOVE BY. LONG TERM...SATURDAY THROUGH TUESDAY...THE CENTRAL U.S. RIDGE/HEAT DOME WILL BUILD EAST FOR THE WEEKEND AND INTO NEXT WEEK. THIS IS LIKELY TO RESULT IN AN EXTENDED PERIOD OF THE HOTTEST TEMPERATURES OF THE SUMMER. THESE CONDITIONS WILL BE AS HOT/HUMID AS WE WERE YESTERDAY...IF NOT MORE SO. THE HEAT DOME WILL EFFECTIVELY CAP THE AIRMASS LOCALLY...WITH LITTLE OR NO CHANCE OF RAINFALL THROUGH THE PERIOD. BAK && .AVIATION... ISSUED 1220 PM CDT TUE JUL 12 2011 PRIMARY FORECAST CONCERN IS FOR CONVECTIVE DEVELOPMENT. AREA OF SHOWERS/STORMS ACROSS EASTERN IOWA HAS PRODUCED AN OUTFLOW BOUNDARY...WITH ASSOCIATED DEVELOPMENT INTO NORTHERN MISSOURI. AM EXPECTING SOME INCREASE IN COVERAGE AS THE STORMS MOVE EAST INTO ILLINOIS...ALONG A SURFACE BOUNDARY AND IN AN AREA OF GREATER INSTABILITY. EASTWARD PROGRESSION ACROSS ILLINOIS IS LESS CLEAR CUT AT THE MOMENT...SO WILL LIMIT VCTS MENTION TO KPIA/KSPI FOR NOW UNTIL TRENDS BECOME MORE CLEAR. SHOULD SEE A DIMINISHING TREND DURING THE EVENING...BUT 12Z MODELS INDICATING SOME POTENTIAL FOR RENEWED CONVECTION EARLY WEDNESDAY MORNING. BULK OF THE RAIN SHOULD BE FURTHER WEST...WITH HIGH PRESSURE TO OUR NORTH BRINGING IN DRIER AIR FROM THE NORTHEAST. CANNOT RULE OUT SOME RAIN MAKING IT AS FAR EAST AS KSPI/KDEC TOMORROW MORNING...BUT CONFIDENCE IS NOT HIGH ENOUGH TO WARRANT INCLUSION AT THIS TIME. GEELHART && .ILX WATCHES/WARNINGS/ADVISORIES... EXCESSIVE HEAT WARNING UNTIL 7 PM CDT THIS EVENING FOR ILZ066>068-071>073. &&
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE LINCOLN IL 312 PM CDT TUE JUL 12 2011 ILZ027>031-037-038-043>046-131100- CHAMPAIGN-DE WITT-KNOX-MARSHALL-MCLEAN-PEORIA-PIATT-STARK- TAZEWELL-VERMILION-WOODFORD- 312 PM CDT TUE JUL 12 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL AND EAST CENTRAL ILLINOIS...MAINLY ALONG AND NORTH OF THE I-74 CORRIDOR. .DAY ONE...TONIGHT SCATTERED THUNDERSTORMS WILL BE POSSIBLE ACROSS THE AREA. THERE IS A SLIGHT RISK OF SEVERE WEATHER...PRIMARILY IN THE FORM OF DAMAGING WINDS AND POSSIBLY LARGE HAIL. HOWEVER...THE MORE SIGNIFICANT SEVERE WEATHER THREAT WILL BE SOUTH OF I-74. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY AFTER A TEMPORARY PERIOD OF COOLER WEATHER...THE HEAT AND HUMIDITY WILL RETURN BY SATURDAY. CURRENT INDICATIONS ARE THAT THE HEAT WAVE WILL BE SIMILAR TO THE MOST RECENT ONE...WITH HEAT INDEX VALUES OVER 105 LIKELY SUNDAY AND MONDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS POSSIBLE THROUGH EARLY EVENING. ILZ036-040-041-047>050-131100- CASS-FULTON-MASON-MENARD-MORGAN-SCHUYLER-SCOTT- 312 PM CDT TUE JUL 12 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF WEST CENTRAL ILLINOIS. .DAY ONE...TONIGHT SCATTERED THUNDERSTORMS ARE EXPECTED ACROSS THE AREA THROUGH TONIGHT. SEVERE WEATHER IS POSSIBLE THIS EVENING...PRIMARILY IN THE FORM OF DAMAGING WINDS AND SOME LARGE HAIL. VERY HEAVY RAIN MAY ALSO RESULT IN LOCALIZED FLOODING...DUE TO THE SLOW MOVEMENT OF SOME OF THE STORMS. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY THUNDERSTORMS MAY LINGER INTO WEDNESDAY MORNING...BUT NO SEVERE WEATHER IS EXPECTED. LINGERING FLOODING ALONG THE ILLINOIS RIVER NEAR BEARDSTOWN WILL SUBSIDE BY EARLY THURSDAY. AFTER A TEMPORARY PERIOD OF COOLER WEATHER...THE HEAT AND HUMIDITY WILL RETURN BY SATURDAY. CURRENT INDICATIONS ARE THAT THE HEAT WAVE WILL BE SIMILAR TO THE MOST RECENT ONE...WITH HEAT INDEX VALUES OVER 105 LIKELY SUNDAY AND MONDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS LIKELY THROUGH THIS EVENING. ILZ042-051>057-061>063-131100- CHRISTIAN-CLARK-COLES-CUMBERLAND-DOUGLAS-EDGAR-LOGAN-MACON- MOULTRIE-SANGAMON-SHELBY- 312 PM CDT TUE JUL 12 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL AND EAST CENTRAL ILLINOIS. .DAY ONE...TONIGHT SCATTERED THUNDERSTORMS ARE EXPECTED ACROSS THE AREA THROUGH TONIGHT. SEVERE WEATHER IS POSSIBLE THIS EVENING...PRIMARILY IN THE FORM OF DAMAGING WINDS AND SOME LARGE HAIL. VERY HEAVY RAIN MAY ALSO RESULT IN LOCALIZED FLOODING...DUE TO THE SLOW MOVEMENT OF SOME OF THE STORMS. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY THUNDERSTORMS MAY LINGER INTO WEDNESDAY MORNING...BUT NO SEVERE WEATHER IS EXPECTED. AFTER A TEMPORARY PERIOD OF COOLER WEATHER...THE HEAT AND HUMIDITY WILL RETURN BY SATURDAY. CURRENT INDICATIONS ARE THAT THE HEAT WAVE WILL BE SIMILAR TO THE MOST RECENT ONE...WITH HEAT INDEX VALUES OVER 105 LIKELY SUNDAY AND MONDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS LIKELY THROUGH THIS EVENING. ILZ066>068-071>073-131100- CLAY-CRAWFORD-EFFINGHAM-JASPER-LAWRENCE-RICHLAND- 312 PM CDT TUE JUL 12 2011 ...EXCESSIVE HEAT WARNING IN EFFECT UNTIL 7 PM CDT THIS EVENING... THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST ILLINOIS. .DAY ONE...TONIGHT THE DAYTIME OPPRESSIVE HEAT INDEX READINGS SHOULD FALL BELOW 100 DEGREES BY SUNSET. SCATTERED THUNDERSTORMS ARE EXPECTED ACROSS THE AREA THROUGH TONIGHT. SEVERE WEATHER IS POSSIBLE THIS EVENING...PRIMARILY IN THE FORM OF DAMAGING WINDS AND SOME LARGE HAIL. VERY HEAVY RAIN MAY ALSO RESULT IN LOCALIZED FLOODING...DUE TO THE SLOW MOVEMENT OF SOME OF THE STORMS. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY THERE WILL BE A CHANCE FOR THUNDERSTORMS ON WEDNESDAY...BUT NO SEVERE WEATHER IS EXPECTED. AFTER A TEMPORARY BREAK...THE HEAT AND HUMIDITY WILL RETURN THIS WEEKEND. CURRENT INDICATIONS ARE THAT THE HEAT WAVE WILL BE SIMILAR TO THE MOST RECENT ONE...WITH HEAT INDEX VALUES OVER 105 LIKELY SUNDAY AND MONDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS LIKELY THROUGH THIS EVENING. GEELHART
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE LINCOLN IL 342 PM CDT TUE JUL 12 2011 ILZ071-122145- CLAY- 342 PM CDT TUE JUL 12 2011 ...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN CLAY COUNTY UNTIL 445 PM CDT... AT 337 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED THAT THUNDERSTORMS WERE RAPIDLY DEVELOPING NEAR XENIA...OR 7 MILES SOUTHWEST OF FLORA...MOVING EAST AT 5 MPH. SMALL HAIL...AND WINDS AROUND 55 MPH ARE EXPECTED WITH THIS STORM. IN ADDITION...UNUSUALLY FREQUENT DEADLY LIGHTNING AND TORRENTIAL RAINFALL WILL BE LIKELY. PEOPLE IN CLAY COUNTY...INCLUDING THE CITIES OF XENIA AND FLORA... SHOULD MONITOR THE WEATHER SITUATION CLOSELY. LISTEN FOR POSSIBLE WARNINGS...AND BE PREPARED TO TAKE APPROPRIATE ACTION SHOULD SEVERE WEATHER THREATEN. LAT...LON 3874 8850 3861 8845 3861 8869 3875 8869 TIME...MOT...LOC 2041Z 274DEG 6KT 3862 8859 CHURCHILL
The Lincoln radar (KILX), 61 km away, was scanning. The volume nearest the first event began at 20:46 UTC.
5 flash flood, 4 thunderstorm wind, 1 hail. Local standard time, as filed.
Power lines were blown down east of Chatham.
Heavy rain of 3.00 to 4.00 inches in a two hour period during the late afternoon produced flash flooding in southwest Clay County. Many rural roads were inundated with water flowing over them, and U.S. Highway 50 was impassable in spots.
Power lines were blown down in Sumner.
Numerous tree branches and power lines were blown down in Lawrenceville.
Numerous tree branches and power lines were blown down in Olney.
Heavy rain of 3.00 to 4.00 inches in a two hour period during the early evening produced flash flooding in western Lawrence County. Many rural roads were inundated with water flowing over them, and U.S. Highway 50 was impassable in spots.
Heavy rain of 3.00 to 4.00 inches in a two hour period during the early evening produced flash flooding in southeast Richland County. Many rural roads around Claremont were inundated with water flowing over them, and U.S. Highway 50 was impassable in spots.
Heavy rain of 3.00 to 6.00 inches in a three hour period during the early evening produced flash flooding in southwest Crawford County. Many rural roads south of Oblong were inundated with water flowing over them.
Heavy rain of 3.00 to 6.00 inches in a three hour period during the early evening produced flash flooding in southeast Jasper County. Many rural roads southeast of Ste. Marie were inundated with water flowing over them.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Illinois in 2011Every state in 2011This day in weather historyWarnings in Illinois, July 2011
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: 333430, 338331, 333431, 333428, 333432, 333434, 338332, 338334, 338335, 338336.