An area of low pressure moved east along Interstate 70 corridor with a warm front extending eastward across southern Illinois and a cold front trailing southwestward along I-44. Storms developed over central Missouri and tracked east into southern Illinois mainly along I-70 with numerous reports of large hail, with some hail stones up to softball size, as well as a few reports of wind damage.
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 LSX wrote it up.
An area of low pressure moved east along Interstate 70 corridor with a warm front extending eastward across southern Illinois and a cold front trailing southwestward along I-44. Storms developed over central Missouri and tracked east into southern Illinois mainly along I-70 with numerous reports of large hail, with some hail stones up to softball size, as well as a few reports of wind damage. Some storms continued to produce hail into the early morning hours of April 29th before diminishing. Overall there were over 100,000 hail damage claims made in Illinois for a total of $665 million in damages.
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 Apr 28, 11:52 AM CST, 2 hours 50 minutes earlier.
AREA FORECAST DISCUSSION...UPDATED AVIATION NATIONAL WEATHER SERVICE ST LOUIS MO 1252 PM CDT SAT APR 28 2012 .SHORT TERM... ISSUED AT 344 AM CDT SAT APR 28 2012 (TODAY) FOCUS FOR TODAY WILL BE TIMING AND LOCATION OF TSRA. MDLS AGREE FAIRLY WELL IN THE OVERALL TRENDS...THO TIMING AND PLACEMENT DIFFER SOMEWHAT. IN GENERAL...EXPECT TSRA TO DEVELOP LATE THIS MORNING IN CNTL MO REGION ALONG/JUST AHEAD OF THE SFC CDFNT AS H85 FLOW BECOMES MORE WLY ADVECTING MORE MOISTURE INTO THE REGION. THIS AREA OF CONVECTION SHUD GRADUALLY PROPAGATE EWD AND S DURING THE AFTERNOON HRS. COVERAGE REMAINS SOMEWHAT UNCERTAIN THRU THE DAY GIVEN THE RATHER WEAK FORCING. BETTER FORCING BEGINS THIS AFTERNOON AS H85 FLOW BECOMES MORE SLY WHICH SHUD INCREASE COVERAGE OF TSRA...OR PERHAPS INITIATE CONVECTION IF TSRA HAVE NOT DEVELOPED EARLIER. ANY TSRA THAT DEVELOP ALONG THE WRMFNT SHUD HAVE ENUF CAPE AND STEEP LAPSE RATES TO POTENTIALLY BECOME SVR WITH HAIL AS THE PRIMARY THREAT...BUT CAN NOT RULE OUT DAMAGING WIND POTENTIAL WHERE SHEAR IS BETTER. TEMPS FOR TODAY WILL BE ANOTHER TRICKY FORECAST. TEMPS IN THE WARM SECTOR COULD REACH LOWER 80S THIS AFTERNOON IF TSRA DEVELOPMENT IS DELAYED SOMEWHAT AND/OR COVERAGE IS LESS THAN ANTICIPATED. WITH SOME BREAKS IN CLOUDS EXPECTED TODAY...HAVE TRENDED A LITTLE WARMER FURTHER N THAN NORMALLY WUD HAVE...BUT THIS IS ALSO DUE TO SOME UNCERTAINTY REGARDING TRACK OF THE SFC LOW. OVERALL...TRENDED TWD THE COOLER GUIDANCE...BUT DID NOT GO BELOW COOLEST NUMBERS. TILLY && .LONG TERM... ISSUED AT 344 AM CDT SAT APR 28 2012 (TONIGHT-MONDAY) UNSETTLED LOOKS TO BE THE BEST DESCRIPTOR FOR THE UPCOMING WEATHER OVER THE REGION...AS FRONTAL BOUNDARY AND NEARLY STATIONARY BELT OF THE WESTERLIES TEAM UP FOR OCCASIONAL SHOWERS AND THUNDERSTORMS. WITH SOME CONVECTIVE FEEDBACK ISSUES AND TOUGH TO TIME SHORTWAVES THE PATTERN IS CERTAINLY A MESSY ONE. HOWEVER...THERE IS GENERAL AGREEMENT IN THE SHORT RANGE SOLUTIONS THAT SURFACE FRONT THAT IS FORECAST TO STALL OUT OVER S MO THIS AFTERNOON/EVENING WILL BEGIN A SLOW NORTHWARD PUSH TONIGHT THROUGH SUNDAY NIGHT AS CUT-OFF LOW OVER N PLAINS DRIFTS NORTH AND ALLOWS HEIGHTS TO INCREASE OVER THE MID MISSISSIPPI VALLEY. WAA-INDUCED LIFT N OF THE FRONT...COMBINED WITH SEVERAL SHORTWAVES TRACKING ACROSS THE REGION IN THE SW UPPER LEVEL FLOW...SHOULD PRODUCE SUFFICIENT UVV WITH THE MODERATELY UNSTABLE AIRMASS TO GENERATE SHOWERS AND THUNDERSTORMS...ESPECIALLY NORTH OF THE FRONT. BY MONDAY SURFACE FRONT SHOULD REMAIN DRAPED OVER THE MID MISSISSIPPI VALLEY...ALTHOUGH MODELS DO NOT AGREE WITH THIS EXACT PLACEMENT. NEVERTHELESS...IT WOULD APPEAR THAT THE SHOWER AND THUNDERSTORM THREAT WILL REMAIN FAIRLY HIGH AS SHORTWAVE ENERGY CONTINUES TO STREAM INTO AREA AND INTERACTD WITH MODERATELY UNSTABLE AIRMASS. TEMPERATURE FORECASTS OVER THE NEXT FEW DAYS AND NIGHTS WILL CONTINUE TO BE A TOUGH CALL DUE TO THE STRONG BAROCLINICITY...CLOUDS...AND RAIN THREAT. FOR SUNDAY...SINCE MOST OF AREA WILL BE N OF SURFACE FRONT TRENDED COOL IN ALL SPOTS EXCEPT THE FAR SOUTH. TEMPERATURES ON MONDAY SHOULD BE MILDER BUT STILL DID NOT GO TOO WARM DUE TO UNCERTAINTY ON EXACT LOCATION OF FRONT...GENERALLY SOME FORM OF THE LM70S. (TUESDAY-FRIDAY) SLOW NORTHWARD SHIFT IN THE MAIN BELT OF THE WESTERLIES WILL ALLOW TEMPERATURES TO REBOUND ABOVE NORMAL....WITH HIGHS IN THE 80S COMMON DURING THE LAST HALF OF THE WEEK. ENOUGH DYNAMICS AND INSTABILITY SHOULD REMAIN OVER THE REGION FOR A PERSISTENT THREAT OF SHOWERS AND THUNDERSTORMS IN MANY AREAS...ALTHOUGH MEDIUM RANGE MODEL BLEND DOES SUGGEST A TEMPORARY LULL IN THE RAIN CHANCES OVER S SECTIONS OF THE CWA AROUND MIDWEEK. TRUETT && .AVIATION... ISSUED AT 1250 PM CDT SAT APR 28 2012 LOW PRESSURE CENTERED OVER CENTRAL MO...JUST EAST OF KCOU AND WILL CONTINUE TO TRACK TO THE EAST. SO FRONTAL BOUNDARY EXPECTED TO SINK JUST A BIT FURTHER TO THE SOUTH...WITH WINDS BECOMING NORTHEAST TO EAST AT TAF SITES BY EARLY THIS EVENING. AS FOR STORMS...SHORTWAVE SLIDING THROUGH REGION HAS BEGUN TO TRIGGER SOME SHOWERS AND STORMS...SO KEPT VCTS MENTION AT KCOU/KUIN SINCE THEY ARE ON BACKSIDE OF SYSTEM...WHILE METRO AREA REMAINS IN THE WARM SECTOR. HAVE TEMPO MVFR CIGS/VSBY MENTION FROM 20Z TO 24Z AT METRO TAFS AS ACTIVITY FIRES UP. STILL EXPECT STORMS TO DIMINISH TOWARDS SUNSET AS WE LOSE HEATING OF THE DAY...WITH ANOTHER ROUND POSSIBLE AFTER 06Z FOR CENTRAL MO...THEN TRACK EAST INTO METRO AREA AFTER 14Z. SPECIFICS FOR KSTL...LOW PRESSURE CENTERED OVER CENTRAL MO...JUST EAST OF KCOU AND WILL CONTINUE TO TRACK TO THE EAST. SO FRONTAL BOUNDARY EXPECTED TO SINK JUST A BIT FURTHER TO THE SOUTH...WITH WINDS BECOMING EAST AT KSTL BY 00Z SUN. AS FOR STORMS...SHORTWAVE SLIDING THROUGH REGION HAS BEGUN TO TRIGGER SOME SHOWERS AND STORMS...SO WITH METRO AREA IN THE WARM SECTOR EXPECT STORMS TO MOVE INTO KSTL AFTER 20Z. THEN STORMS TO DIMINISH TOWARDS SUNSET AS WE LOSE HEATING OF THE DAY...WITH ANOTHER ROUND POSSIBLE AFTER 14Z SUNDAY...SO ADDED VCSH MENTION FOR NOW. WITH FRONTAL BOUNDARY LINGERING NEARBY THROUGH THE PERIOD...COULD SEE CIGS DIP DOWN TO IFR TOWARDS DAYBREAK...BUT CONFIDENCE IS LOW...SO JUST HAVE MVFR CIGS MENTIONED FOR NOW. BYRD && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && WFO LSX
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE ST LOUIS MO 155 PM CDT SAT APR 28 2012 ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027- 034>036-041-042-047>052-059>065-072>075-084-085-099-291200- 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 MO- LEWIS MO-SHELBY MO-MARION MO-MONROE MO-RALLS MO-PIKE MO-BOONE MO- AUDRAIN MO-MONITEAU MO-COLE MO-OSAGE MO-CALLAWAY MO-MONTGOMERY MO- LINCOLN MO-GASCONADE MO-WARREN MO-ST. CHARLES MO-FRANKLIN MO- ST. LOUIS MO-ST. LOUIS CITY MO-JEFFERSON MO-CRAWFORD MO- WASHINGTON MO-ST. FRANCOIS MO-STE. GENEVIEVE MO-IRON MO- MADISON MO-REYNOLDS MO- 155 PM CDT SAT APR 28 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN AND CENTRAL MISSOURI AS WELL AS WEST CENTRAL AND SOUTHWEST ILLINOIS. .DAY ONE...THIS AFTERNOON AND TONIGHT THERE IS A CHANCE FOR THUNDERSTORMS TODAY PRIMARILY NEAR THE INTERSTATES 44 AND 70 CORRIDORS...AND ACROSS THE ENTIRE AREA TONIGHT. A FEW SEVERE STORMS THROUGH EARLY THIS EVENING WILL BE LIKELY. LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY THREATS...ALTHOUGH THERE WILL BE AN ISOLATED TORNADO POSSIBILITY WITH THE MOST INTENSE THUNDERSTORMS. FOR FURTHER INFORMATION ON CONVECTIVE WATCHES...PLEASE REFER TO THE LATEST STORM PREDICTION CENTER WATCH PRODUCTS. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY A THREAT OF THUNDERSTORMS WILL PERSIST ACROSS THE REGION FOR MUCH OF THE NEW WEEK AS A FRONTAL BOUNDARY REMAINS DRAPED ACROSS THE CENTRAL U.S. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS LIKELY THROUGH EARLY THIS EVENING. TES
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
331 PM CDT SAT APR 28 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0325 PM HAIL BRIDGETON 38.77N 90.43W
04/28/2012 E1.25 INCH ST. LOUIS MO TRAINED SPOTTER
3 MILES WEST OF LAMBERT
&&
MILLERPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
332 PM CDT SAT APR 28 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0328 PM HAIL FLORISSANT 38.80N 90.32W
04/28/2012 E2.00 INCH ST. LOUIS MO TRAINED SPOTTER
NEAR INTERSECTION OF CHARBONIER AND SHACKELFORD
&&
MILLERPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
335 PM CDT SAT APR 28 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0335 PM HAIL FLORISSANT 38.80N 90.32W
04/28/2012 M1.75 INCH ST. LOUIS MO TRAINED SPOTTER
&&
KANOFSKYPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
336 PM CDT SAT APR 28 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0315 PM HAIL 2 N ST. CHARLES 38.82N 90.52W
04/28/2012 E1.50 INCH ST. CHARLES MO TRAINED SPOTTER
&&
MILLERPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
340 PM CDT SAT APR 28 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0325 PM HAIL BLACK JACK 38.80N 90.26W
04/28/2012 E0.88 INCH ST. LOUIS MO TRAINED SPOTTER
&&
MILLERPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
342 PM CDT SAT APR 28 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0342 PM HAIL FERGUSON 38.75N 90.30W
04/28/2012 E1.25 INCH ST. LOUIS MO TRAINED SPOTTER
&&
GOSSELINThe St Louis radar (KLSX), 45 km away, was scanning. The volume nearest the first event began at 20:41 UTC.
31 hail, 5 thunderstorm wind. Local standard time, as filed.
There were numerous reports of large hail across Granite City. The largest hail stones were tennis ball size.
There were numerous reports of large hail across Collinsville. The largest hail stones were tennis ball size. Golfball size hail was reported at Cahokia Mounds State Park.
There were numerous reports of large hail across Fairview Heights. The largest hail stones were tennis ball size reported near the intersection of I-64 and Bunkum Road. Also, numerous roofs sustained shingle damage and numerous cars sustained dents from the hail stones.
There were numerous reports of large hail across O'Fallon. The largest hail stones were three and a half inches by two inch disc shaped stones. Baseball sized hail was reported at Scott Air Force Base.
There were numerous reports of large hail across Lebanon. The largest hail stones were baseball size. Numerous car windows and several windows on homes sustained damage.
Thunderstorm winds blew down several signs along I-64. Also, a few large trees were snapped off on the southeast side of O'Fallon.
Thunderstorm winds blew down numerous large tree limbs.
There were numerous reports of large hail across Belleville and Swansea. The largest hail stones reported were three inches in diameter. There were numerous reports of damage to vehicles from the hail.
A swath of large hail was reported in the New Baden area. There were numerous reports of vehicles with their windows broken both in town and along Interstate 64 between mile markers 27 and 30. The largest hail stones were baseball size.
Thunderstorm winds blew down several power lines and large tree limbs.
Enough hail fell that it looked like it had snowed in Farina. Dense fog briefly developed due to the large amounts of hail.
Thunderstorm winds destroyed two garages in town and blew the roofs off of a couple of barns. Also, some homes sustained shingle damage and several trees were blown over.
Hail was covering the ground.
Hail was covering the ground on the southside of Marissa.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Illinois in 2012Every state in 2012This day in weather historyWarnings in Illinois, April 2012
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: 372451, 372452, 373122, 373126, 373127, 373156, 373157, 373160, 373159, 373158, 373169, 373173, 373170, 373174, 373171, 373172, 373175, 373176, 373177, 373178, 373179, 373180, 377353, 377354, 377355, 377357, 377358, 377359, 377362, 377361, 377363, 377364, 377366, 377367, 377375, 377377.