Low pressure tracked across eastern Iowa and northwest Illinois during the evening hours of April 25, 2012. A warm front also moved north into the area triggering severe thunderstorms across extreme southeast Iowa and extreme northeast Missouri.
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 DVN wrote it up.
Low pressure tracked across eastern Iowa and northwest Illinois during the evening hours of April 25, 2012. A warm front also moved north into the area triggering severe thunderstorms across extreme southeast Iowa and extreme northeast Missouri. These storms dumped large hail and even produced a tornado near Kahoka, Missouri. There were several reports of golf ball size hail in extreme southeast Iowa.
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 Quad Cities, IA wrote its last area forecast discussion before the first event at Apr 25, 5:11 PM CST, 1 hour 2 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE QUAD CITIES IA IL 611 PM CDT WED APR 25 2012 .AVIATION... LOW PRESSURE WILL SLIDE SOUTHEAST OF EASTERN IOWA EARLY THIS EVENING...RESULTING IN NORTH TO NORTHEAST WINDS FOR THE NEXT 24 HOURS. WIDESPREAD VFR CONDITIONS ARE EXPECTED...WITH ONLY CIRRUS AND SOME SCATTERED MID CLOUDS THROUGH THROUGH THE NIGHT AND SPOTTY FAIR WEATHER CUMULUS ABOVE 5000 FT TOMORROW. THERE IS A SLIGHT CHANCE STRATUS COULD AFFECT NORTHEAST IOWA TOWARDS MORNING FOR A FEW HOURS...POSSIBLY AFFECTING THE DBQ AIRPORT. HOWEVER...WILL LEAVE THIS OUT FOR NOW...AND SHOW CLEAR SKIES TOMORROW. ERVIN && .UPDATE... THE FORCING IS WEAK THIS EVENING...AND LARGELY ALREADY PASSED BY. CAPPING HAS REMAIN STRONG...WITH ONLY ONE STORM ALLOWED NEAR THE FRONT OVER CENTRAL ILLINOIS. A FEW WEAK CELLS NEAR OTTUMWA APPEAR TO BE THE LAST GASP OF FORCING. THUS..WE UPDATED AN HOUR OR MORE AGO TO GO DRY...EXCEPT A SLIGHT CHANCE OVER FAR SOUTHEAST IOWA AND WEST CENTRAL ILLINOIS/NE MO THROUGH 00Z. ERVIN && .PREV DISCUSSION... /ISSUED 315 PM CDT WED APR 25 2012/ SYNOPSIS... LATEST SFC ANALYSIS WAS INDICATING MAIN UPSTREAM LOW PRESSURE CENTER NEAR THE DSM AREA WITH ASSOCIATED WARM FRONT BUCKLING UP INTO SOUTH CENTRAL MN...AND THEN DRAPED BACK SOUTHEASTWARD THROUGH MACOMB IL AND INTO SOUTHEASTERN IL. SOME SFC DPT POOLING DRIVING VALUES INTO THE LOWER 60S IN SOUTH CENTRAL TO SE IA ATTM...WHILE MUCH OF THE REST OF THE AREA DPTS HAVE MIXED DOWN AND REMAINED WELL DOWN IN THE 50S. BEST SFC PRESSURE FALLS/BULLS-EYE ARE STARTING TO MOVE EAST OF THE DVN CWA TOWARD EAST CENTRAL IL/WEST CENTRAL INDIANA. WV IMAGERY AS WELL AS VIS SATELLITE LOOP SUGGESTING UPPER VORT ALMOST ON TOP OF THE DVN CWA ALREADY...WHICH MEANS BEST FORCING SHOULD START TO FOLLOW THE PRESSURE FALL PATTERNS. ELEVATED CLOUD COVER/SOME HIGH BASED SHOWERS...AND IMPRESSIVE SFC BASED CIN VALUES CONTINUE TO REIGN ACRS THE CWA WITH THE CLOUD COVER AND SOME EVAPO-COOLING IMPEDING THE ARM UP TO CONVECTIVE TEMPS ESPECIALLY IN THE SECTOR SOUTH OF THE WARM FRONT. SHORT TERM...TONIGHT AND THURSDAY... TONIGHT...MUCH OF THE PARAMETERS ONGOING DISCUSSED ABOVE IN THE SYNOPSIS SUGGESTS A LIMITED THREAT OF STRONG SFC BASED CONVECTION DEVELOPING IN THE CWA...OR EVEN ELEVATED STORMS NORTH OF THE WARM FRONT THROUGH EARLY EVENING. NORMAL NOCTURNAL PROCESSES MAY EVENTUALLY DRIVE AN ELEVATED STORM EVENT BY MID TO LATE EVENING BUT MOST OF THAT WOULD LIKELY TAKE PLACE EAST AND SOUTHEAST OF THE LOCAL AREA OF CONCERN. WILL IGNORE MOST OF THE SHORT RANGE MODELS WHICH ARE TOO AGGRESSIVE WITH LOW TO MID LEVEL MOISTURE FETCH/OVERBLOWN CAPES AND INSTABILITY. ONLY THE HIRES ARW MODEL IS CLOSE TO HANDLING THE CURRENT SFC BASED MOISTURE VALUES CORRECTLY...AND THIS MODEL IGNITES INITIAL CONVECTION ACRS CENTRAL IL AROUND 7 PM CDT...AND THEN FURTHER DEVELOPS IT AS IT SCOOTS OFF TOWARD THE OH VALLEY THROUGH MIDNIGHT. WILL STILL KEEP CHC POPS GOING ESPECIALLY ACRS THE EAST/ SOUTHEAST HALF THROUGH MID EVENING IN THE POSSIBLE CONVECTIVE INITIATION ZONE UNTIL LINGERING FORCING FROM PASSING CYCLONE AND VORT ALOFT MIGRATES TO THE EAST. BUT ALL WE MAY GET IS THE CURRENT HIGH BASED PASSING SHOWERS AND SPRINKLES. ANOTHER LOW CHANCE FOR SOME DEVELOPMENT FRO AT LEAST ISOLATED SHOWERS/STORMS RIGHT BEHIND THE PASSING LOW AS WAKE NORTHWEST FLOW KICKS IN ON WANING CAP/S WESTERN FRINGE BY MID TO LATE EVENING...BUT WILL NOT PUT POPS IN FOR THAT POSSIBILITY AND LET EVENING SHIFT ASSESS IF THIS PROCESS CAN REALLY UNFOLD. IN-BUILDING HIGH PRESSURE AND NW TO NORTH FLOW COOL-ADVECTS LOWS INTO THE MID 40S IN THE NORTHEAST...TO THE LOW TO MID 50S IN THE SOUTH BY THU MORNING. THURSDAY...HIGH PRESSURE AND IT/S IN-BUILDING GRADIENT CONTINUE ON THU FOR BREEZY NORTH TO NORTHEAST SFC WINDS BUT AT LEAST MOSTLY SUNNY SKIES. DESPITE SOME ROBUST CAA...DEEP MIXING ALONG WITH THE INSOLATION WILL TRANSLATE TO THU HIGHS IN THE LOWER 60S NORTH OF HWY 30...TO THE MID AND UPPER 60S ALONG AND SOUTH OF I80. ..12.. LONG TERM...THURSDAY NIGHT THROUGH NEXT WEDNESDAY... GENERALLY BELOW NORMAL TO END THE MONTH OF APRIL... WITH TWO MAIN WINDOWS FOR RAIN... ONE DEVELOPING FRI LINGERING INTO SAT AND THE OTHER LATER MON INTO TUE. THU NGT... HAVE REMOVED RAIN CHCS WITH MODELS SHOWING DEEP DRY EASTERLY FETCH FROM BENEATH GREAT LAKES RIDGING. DESPITE INCREASE IN CLOUDS... LOWS NEAR OR EVEN JUST BELOW COOL SIDE WITH MID 30S NE TO MID 40S SW. FRI-FRI NGT... DRY EASTERLY FETCH TO SLOW SATURATION AND ONSET OF MEASURABLE RAIN FOR MANY AREAS UNTIL AFTN... CONTINUING FRI NGT. BEST COVERAGE AND AMOUNTS SUGGESTED NORTH OF HWY 34 ATTIM... AND MOSTLY LIGHT AT THAT ALTHOUGH SOME MODERATE AMOUNTS POSSIBLE LATE AT NGT INTO SAT WITH APPROACH OF MID LEVEL SHORTWAVE. DUE TO SLOWER ARRIVAL OF RAIN FRI HAVE NUDGED UP HIGHS SOME. STILL A TRICKY MAX TEMP FCST FOR FRI WITH EVAPORATIVE COOLING EFFECTS WITH VIRGA AND SPRINKLES FIRST HALF OF DAY. TEMPS NEAR STEADY FRI NGT WITH CLOUDS AND RAIN... WITH COOLEST READINGS NORTH AND WARMEST IN THE SOUTH WHERE COULD EVEN RISE SOME DEPENDING ON MOVEMENT OF WARM FRONT... WITH POTENTIAL FOR NEEDING TO EXPAND OR RAISE MIN TEMP GRADIENT NORTH TO SOUTH. SAT-SAT NGT...RAIN TAPERING OFF SAT AM BUT WILL CONTINUE WITH CHCS REST OF DAY INTO SAT NGT WITH INVERTED SFC TROUGH. WARMEST HIGHS WILL BE ACROSS THE SOUTH DUE TO WARMER START AND EARLIER END TO ANY RAIN... WHILE NEAR STEADY OR SLOW RISE ON TEMPS FAR NORTH. HAVE EXPANDED HIGH TEMP GRADIENT SOME... WITH MID/UPPER 40S NORTH TO UPPER 50S FAR SOUTH. DEPENDING ON ANY SUNSHINE AND MOVEMENT OF WARM FRONT CANT RULE OUT 60S FAR SOUTH. SUN-TUE... PATTERN RECYCLES ITSELF WITH YET ANOTHER LARGE HIGH SETTLING INTO THE GREAT LAKES THRUSTING REGION IN DEEP LOW LEVEL COOL AND DRY EASTERLY FETCH SUN INTO MON. LATE MON THROUGH TUE WILL BRING NEXT APPRECIABLE RAIN CHCS WITH NEXT BARRAGE OF PACIFIC ENERGY. WILL HOWEVER NEED TO BE WATCHFUL FOR SLOWING ARRIVAL GIVEN DRY EASTERLY FETCH. TEMPS LOOK TO MODERATE NEAR TO A BIT ABOVE NORMAL BY THE END OF THE PERIOD AND JUST BEYOND... WITH FLOW PATTERN BECOMING SEMI- ZONAL TO WSW. ..05.. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && ERVIN
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE QUAD CITIES IA IL 342 PM CDT WED APR 25 2012 IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007- 009-015>018-024>026-034-035-MOZ009-010-261000- BENTON IA-BUCHANAN IA-BUREAU IL-CARROLL IL-CEDAR IA-CLARK MO- CLINTON IA-DELAWARE IA-DES MOINES IA-DUBUQUE IA-HANCOCK IL- HENDERSON IL-HENRY IA-HENRY IL-IOWA IA-JACKSON IA-JEFFERSON IA- JO DAVIESS IL-JOHNSON IA-JONES IA-KEOKUK IA-LEE IA-LINN IA-LOUISA IA- MCDONOUGH IL-MERCER IL-MUSCATINE IA-PUTNAM IL-ROCK ISLAND IL- SCOTLAND MO-SCOTT IA-STEPHENSON IL-VAN BUREN IA-WARREN IL- WASHINGTON IA-WHITESIDE IL- 342 PM CDT WED APR 25 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL ILLINOIS...NORTHWEST ILLINOIS...WEST CENTRAL ILLINOIS...EAST CENTRAL IOWA...NORTHEAST IOWA...SOUTHEAST IOWA AND NORTHEAST MISSOURI. .DAY ONE...TONIGHT THERE WILL BE A CHANCE FOR SHOWERS AND ISOLATED THUNDERSTORMS TO MOVE ACROSS PORTIONS OF THE OUTLOOK AREA THROUGH MID EVENING. THERE IS STILL A LINGERING LOW CHANCE FOR A STRONG TO SEVERE STORM TO DEVELOP THIS EVENING EAST OF THE MISSISSIPPI RIVER...BUT LATEST INDICATIONS SUGGEST THE BEST CHANCE FOR STRONG TO SEVERE STORMS WILL OCCUR TO THE EAST AND SOUTHEAST OF THE OUTLOOK AREA TONIGHT. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY THUNDERSTORMS MAY BE POSSIBLE NEXT TUESDAY. IT IS TOO SOON TO DETERMINE THE POTENTIAL FOR SEVERE WEATHER. .SPOTTER INFORMATION STATEMENT... THERE IS LOW CHANCE FOR THE NEED OF SPOTTER ACTIVATION THIS EVENING EAST OF THE MISSISSIPPI RIVER. 12
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE QUAD CITIES IA IL 641 PM CDT WED APR 25 2012 IAZ087-088-098-099-MOZ010-260045- CLARK-HENRY-JEFFERSON-LEE-VAN BUREN- 641 PM CDT WED APR 25 2012 ...ISOLATED STRONG THUNDERSTORMS... AT 638 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED THAT THUNDERSTORMS WERE RAPIDLY DEVELOPING NEAR DOUDS/LEANDO...OR 12 MILES NORTHWEST OF KEOSAUQUA...MOVING EAST SOUTHEAST AT 25 MPH. * THE THUNDERSTORM WILL BE NEAR... DOUDS/LEANDO AROUND 645 PM CDT... BIRMINGHAM AROUND 700 PM CDT... KEOSAUQUA AROUND 705 PM CDT... BONAPARTE AROUND 725 PM CDT... 6 MILES SOUTH OF HILLSBORO AROUND 730 PM CDT... NICKEL SIZE HAIL...WINDS GREATER THAN 40 MPH...AND BRIEF HEAVY RAIN...ARE EXPECTED WITH THESE STORMS. LAT...LON 4085 9154 4057 9166 4069 9218 4095 9218 TIME...MOT...LOC 2340Z 286DEG 23KT 4084 9213 ERVIN
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
711 PM CDT WED APR 25 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0647 PM HAIL 1 W SELMA 40.87N 92.17W
04/25/2012 M0.50 INCH VAN BUREN IA TRAINED SPOTTER
RELAYED BY NWS DES MOINES.
&&
GROSSThe Quad Cities radar (KDVN), 151 km away, was scanning. The volume nearest the first event began at 00:13 UTC.
9 hail. Local standard time, as filed.
A trained spotter reported nickel size hail but mostly pea size hail near Kilbourn.
County sheriff reported golf ball size hail near Lebanon.
A trained spotter reported nickel size hail falling for 3 minutes near Pittsburgh.
A trained spotter reported lots of dime size hail falling just southeast of Keosauqua.
Hail the size of quarters was reported by a trained spotter northwest of Bonaparte.
Golf ball size hail was observed by a trained spotter southeast of Cantril.
A trained spotter reported hail the size of quarters but mostly the size of nickels.
A trained spotter reported golf ball size hail northeast of Cantril.
A trained spotter measured dime size hail near Keokuk.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2012Every state in 2012This day in weather historyWarnings in Iowa, 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: 372984, 372988, 372989, 372990, 372991, 372993, 372994, 372996, 372998.