The warm front from the previous night lifted north of the state as low pressure pushed northeast out of Kansas across northwest Iowa. The atmosphere became quite unstable.
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 DMX wrote it up.
The warm front from the previous night lifted north of the state as low pressure pushed northeast out of Kansas across northwest Iowa. The atmosphere became quite unstable. Lifted indices fell to -6 to -8, with CAPE values in the 1000 to 2000 J/kg range. CAPE in the -10 to -30 C. layer of the atmosphere was between 200 and 500 J/kg. Downdraft CAPE was in the 400 to 700 J/kg range. The effective shear was between 35 and 55 kts. The freezing level was consistent with what it had been the previous few events, at 11,900 feet. Thunderstorms developed in several lines. The main issue with the thunderstorms was heavy rain as precipitable water values were around 1.6 inches. The 850 mb feed into the system was between 45 and 55 kts. Spotty reports of severe wind were received along the line with some relatively minor damage. Some farm outbuilding damage occurred with the high winds and a few trees were blown over. The roof and siding were both damaged on a house at Sun Valley Lake in Ringgold County as a brief tornado touched down there. Part of the roof was actually removed by 80 MPH straight line winds. Many of the storms produced hail, however it remained below severe limits. Flooding was widespread with flash flooding reported in several counties. Rainfall of 4 to 7 inches occurred in a few areas, especially in Guthrie and Audubon Counties. A band widespread 2 to 4 inch rainfall extended all the way across the CWA from the southwest corner to the northeast in the Waterloo area. Some of the heavier totals included 8.5 inches in Waterloo, 7.4 inches in Hudson, both in Black Hawk County, and 7 inches in Hardin County in the Whitten area. Numerous reports of 24 to 36 hour rainfall totals were received. They ranged from 3 1/4 to over 8 inches. As the thunderstorms were moving east of the area, lightning struck a house in Altoona setting it on fire. The house was severely damaged. Nobody was home at the time, however fire fighters were able to save the family dog.
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 Des Moines, IA wrote its last area forecast discussion before the first event at Apr 25, 2:25 AM CST, 3 hours 5 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DES MOINES IA 325 AM CDT SAT APR 25 2009 .SHORT TERM /TODAY/... FRONTAL BOUNDARY THROUGH ABOUT THE NORTHWESTERN TWO THIRDS OF THE CWA...CURRENTLY STRETCHING FROM NEAR OSCEOLA NORTHEASTWARD TOWARD NEWTON WITH MUCH OF THE TSRA ACTIVITY ACROSS THE CWA POST FRONTAL ACROSS THE NORTHERN CWA. POST-FRONTAL ACTIVITY SITUATED ALONG AND BEHIND THE FRONT ALOFT...IN AREA OF ISENTROPIC LIFT. THIS AREA OF LIFT TO DROP SOUTHEASTWARD THROUGH THE DAY...AS THE SFC FRONT PROGRESSES THROUGH THE REMAINDER OF THE CWA AS WELL. CHANCE FOR THUNDER POSSIBLE...WITH ELEVATED INSTABILITY THROUGHOUT THE DAY. SLIGHT RISK STILL ACROSS THE FAR SOUTHEAST WHERE FRONTAL BOUNDARY WILL MOVE THROUGH TODAY...OTHERWISE ANY SEVERE THREATS REMAIN MAINLY TO THE EAST AND SOUTH OF THE CWA. POST FRONTAL TEMPERATURES ALOFT MUCH COOLER THAN YESTERDAY...HOVERING IN THE SINGLE DIGITS THEREFORE EXPECT MAX TEMPS TODAY CLOSER TO SEASONAL AVERAGES VERSUS THE NEAR RECORD AND RECORD MAX HIGHS ACROSS THE AREA YESTERDAY. .LONG TERM.../TONIGHT-FRIDAY/ NO SIGNIFICANT CHANGES WERE MADE TO THIS PERIOD. MAIN SHORTWAVE TROUGH ENERGY OVER THE SRN ROCKIES EARLY TONIGHT WILL MOVE NORTHEAST THROUGH THE NRN PLAINS SUNDAY...WHILE PRECEDING AND TRAILING MINOR SHORWAVES IN THE SOUTHWESTERLY FLOW ALOFT MOVE OVER IOWA. MEANWHILE THE FRONT MOVING THROUGH THE AREA EARLY TODAY WILL BE STALLED OVER NRN MO THIS EVENING...THEN BEGIN MOVING BACK NORTH ACROSS THE AREA LATER TONIGHT. AS THE LOW LEVEL JET INCREASES LATE TONIGHT AND ALONG WITH STRONG THETA-E ADVECTION AND INCREASING KINEMATIC FORCING AHEAD OF WEAK UPPER LEVEL WAVE...EXPECT SHOWERS AND THUNDERSTORMS TO INCREASE IN COVERAGE WHILE THE WHOLE AREA MOVES NORTH. SVR STORMS ARE POSSIBLE GIVEN MAGNITUDE OF DEEP LAYER SHEAR...BUT WOULD LIKELY ONLY HAVE ISOLATED MARGINALLY SEVERE HAILERS. SUNDAY IS NOT AS CLEAR IN TERMS OF SHOWERS/TSTM COVERAGE AND INTENSITY AS THE DAYTIME HOURS SIT BETWEEN THE MAIN FORCING EVENTS OF SATURDAY NIGHT AND SUNDAY NIGHT. THERE IS ALSO A QUESTION OF CLOUD COVER INHIBITING INSOLATION AND THEREFORE THE ABILITY FOR THE LOWER LEVELS TO DESTABILIZE. NEVERTHELESS...WILL KEEP POPS IN THE HIGH LIKELY CATEGORY FOR A GENERAL THREAT OF SHOWERS/STORMS AT ANY TIME DURING THE DAY WITH AREA IN WARM...HUMID AND AT LEAST WEAKLY UNSTABLE WARM SECTOR. SOUTHERLY SFC FLOW WILL BE GUSTY AGAIN...MUCH LIKE FRIDAY. SEVERE ORGANIZED STORMS WILL CERTAINLY BE LIKELY LATE IN THE DAY NEAR THE ADVANCING COLD FRONT IF WE CAN DESTABILIZE...AGAIN GIVEN THE MAGNITUDE OF DEEP LAYER SHEAR. KINEMATIC FORCING ALOFT AND LOW LEVEL CONVERGENCE REALLY INCREASE SUNDAY NIGHT ACROSS CENTRAL IOWA IN RESPONSE TO UPPER LEVEL DIVERGENCE AHEAD OF APPROACHING UPPER LEVEL TROUGH AXIS...AND STRONG LIFT IN STRENGTHENING ENTRANCE REGION TO UPPER LEVEL JET MOVING ALMOST DIRECTLY OVER IOWA. ALL OF THIS FORCING ACTING ON AN AIRMASS CONTAINING NEARLY DOUBLE THE NORMAL PRECIPITABLE WATER CONTENT FOR THIS TIME OF YEAR WILL YIELD AN ACTIVE FRONTAL ZONE OF SHOWERS AND THUNDERSTORMS WITH THE POTENTIAL TO PRODUCE HEAVY RAINFALL. THE GFS AND ECMWF ARE ADVERTISING 2 TO 3 INCHES OF RAIN ALONE SUNDAY NIGHT...NEVERMIND WHAT FALLS TONIGHT AND SUNDAY. THEY ARE ON THE HIGHER END OF THE MODEL SUITE...BUT OTHER MODELS ARE NOT FAR BEHIND. THE AXIS OF HEAVY RAIN WILL SHIFT SOUTHEAST DURING SUNDAY NIGHT AS THE COLD FRONT EDGES EASTWARD. BY MONDAY...COOLER AND DRIER AIR WILL BE FILTERING IN...LEAVING ONLY THE FAR SOUTHEAST A LINGERING CHANCE OF RAIN EARLY IN THE DAY. WOULD NOT BE SURPRISED TO SEE A FLOOD WATCH ISSUED AT SOME POINT TODAY...FOR SUNDAY NIGHT. BUT GIVEN SOME UNCERTAINTIES INHERENT WITH CONVECTIVE PRECIPITATION PATTERNS...WILL SIMPLY CONTINUE THE HYDROLOGIC OUTLOOK /ESFDMX/ FOR NOW. THE EARLY TO MIDDLE OF THE WEEK WILL FEATURE GENERALLY DRY WEATHER WITH TEMPERATURES A FEW DEGREES BELOW NORMAL. MORE ACTIVE WEATHER COULD AFFECT THE REGION BEGINNING WEDNESDAY OR THURSDAY. && .AVIATION...25/06Z NAILING DOWN CONVECTIVE TRENDS THIS TAF PERIOD WILL BE QUITE A CHALLENGE. BASED ON RADAR TRENDS...HAVE INCLUDED A NEAR TERM MENTION OF TSRA AT KMCW/KOTM...WITH A LESSOR CHANCE AT KFOD. BEYOND THE NEAR TERM...AM GENERALLY FOLLOWING THE NAM TRENDS WITH A PERIOD OF SHRA FROM NORTH TO SOUTH THROUGH THE MORNING...THEN INTRODUCING TSRA AGAIN THIS AFTERNOON AT KDSM/KOTM. SOME SHOWERS MAY SPREAD INTO THE NORTHERN SITES AFTER 26/00Z. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && SHORT TERM...ALBRECHT LONG TERM...MOYER AVIATION...KINNEY
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 513 AM CDT SAT APR 25 2009 IAZ004>007-015>017-023>025-033>035-044-045-261015- EMMET-KOSSUTH-WINNEBAGO-WORTH-PALO ALTO-HANCOCK-CERRO GORDO- POCAHONTAS-HUMBOLDT-WRIGHT-SAC-CALHOUN-WEBSTER-CRAWFORD-CARROLL- 513 AM CDT SAT APR 25 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHERN AND NORTHWESTERN CENTRAL IOWA. .DAY ONE...TODAY AND TONIGHT SCATTERED NON SEVERE THUNDERSTORMS WILL OCCUR...MAINLY THIS MORNING AND AGAIN LATER TONIGHT. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY THUNDERSTORMS ARE LIKELY SUNDAY...WITH DIMINISHING CHANCES SUNDAY NIGHT. THE THREAT OF SEVERE WEATHER IS LOW. THUNDERSTORMS ARE POSSIBLE AGAIN WEDNESDAY THROUGH FRIDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED AT THIS TIME. IAZ026>028-036>039-046>050-057>062-070>075-081>086-092>097-261015- FRANKLIN-BUTLER-BREMER-HAMILTON-HARDIN-GRUNDY-BLACK HAWK-GREENE- BOONE-STORY-MARSHALL-TAMA-AUDUBON-GUTHRIE-DALLAS-POLK-JASPER- POWESHIEK-CASS-ADAIR-MADISON-WARREN-MARION-MAHASKA-ADAMS-UNION- CLARKE-LUCAS-MONROE-WAPELLO-TAYLOR-RINGGOLD-DECATUR-WAYNE- APPANOOSE-DAVIS- 513 AM CDT SAT APR 25 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE SOUTHEAST TWO THIRDS OF CENTRAL IOWA. .DAY ONE...TODAY AND TONIGHT SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY...WITH A LITTLE MORE COVERAGE OF THUNDERSTORMS TONIGHT. ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE...MAINLY SOUTHEAST OF A LINE FROM OSKALOOSA TO MOUNT AYR...WITH LARGE HAIL THE MAIN THREAT. LOCALLY HEAVY RAINFALL IS ALSO POSSIBLE TONIGHT. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY THUNDERSTORMS ARE LIKELY SUNDAY...ESPECIALLY IN THE AFTERNOON...WITH GREATER COVERAGE SUNDAY NIGHT. SEVERE THUNDERSTORMS ARE AGAIN POSSIBLE WITH LARGE AND DAMAGING WINDS THE MAIN THREATS IN THE AFTERNOON AND NIGHT. WIDESPREAD HEAVY RAIN IS EXPECTED SUNDAY NIGHT...WHICH COULD LEAD TO MINOR TO MODERATE RIVER AND TRIBUTARY FLOODING...AND POSSIBLY LOCALIZED FLASH FLOODING. THUNDERSTORMS ARE POSSIBLE AGAIN WEDNESDAY THROUGH FRIDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED AT TIMES LATER TODAY...TONIGHT AND SUNDAY. MOYER
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
342 AM CDT SAT APR 25 2009
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0551 PM HAIL 5 SE MANLY 43.25N 93.12W
04/24/2009 E0.88 INCH CERRO GORDO IA TRAINED SPOTTER
DIME TO NICKEL HAIL.
0551 PM HAIL 4 NNW LAKE CORNELIA 42.83N 93.72W
04/24/2009 E1.00 INCH WRIGHT IA TRAINED SPOTTER
NICKEL TO QUARTER HAIL REPORTED.
0603 PM HAIL 5 NNW ROCKWELL 43.05N 93.21W
04/24/2009 E1.00 INCH CERRO GORDO IA BROADCAST MEDIA
HAIL REPORT NEAR ROCKWELL RELAYED BY KIMT TV.
0605 PM HAIL 1 S MASON CITY 43.14N 93.20W
04/24/2009 E0.88 INCH CERRO GORDO IA TRAINED SPOTTER
A LOT OF PEA TO NICKEL HAIL
0619 PM HAIL 4 S MESERVEY 42.86N 93.48W
04/24/2009 E1.00 INCH FRANKLIN IA TRAINED SPOTTER
0628 PM HAIL 4 NE ALEXANDER 42.85N 93.42W
04/24/2009 E1.00 INCH FRANKLIN IA STORM CHASER
NUMEROUS QUARTER HAIL REPORTED
0647 PM HAIL ATLANTIC 41.40N 95.01W
04/24/2009 E0.88 INCH CASS IA TRAINED SPOTTER
HAIL UP TO NICKEL SIZE COVERING MOST YARDS.
0705 PM HAIL 3 S GRAND JUNCTION 41.99N 94.24W
04/24/2009 E1.00 INCH GREENE IA TRAINED SPOTTER
0711 PM HAIL 4 NNE HANSELL 42.81N 93.07W
04/24/2009 E1.00 INCH FRANKLIN IA TRAINED SPOTTER
QUARTER SIZED HAIL. CORRECTED TIME AND LOCATION FROM
SPOTTER.
0714 PM HAIL 3 SSW STRATFORD 42.24N 93.95W
04/24/2009 E0.75 INCH WEBSTER IA TRAINED SPOTTER
0720 PM HAIL 2 ENE AREDALE 42.84N 92.96W
04/24/2009 E1.00 INCH BUTLER IA TRAINED SPOTTER
0722 PM HAIL 2 E AREDALE 42.83N 92.96W
04/24/2009 E1.25 INCH BUTLER IA TRAINED SPOTTER
HAIL COVERING THE GROUND.
0723 PM HAIL 5 SW GREENE 42.84N 92.88W
04/24/2009 E1.00 INCH BUTLER IA TRAINED SPOTTER
ALL HAIL...VERY LITTLE RAIN FALLING.
0753 PM HAIL 3 ESE ALLISON 42.74N 92.73W
04/24/2009 E1.00 INCH BUTLER IA TRAINED SPOTTER
0802 PM HAIL CLARKSVILLE 42.78N 92.67W
04/24/2009 M1.25 INCH BUTLER IA BROADCAST MEDIA
KIMT SPOTTER REPORT.
0820 PM HAIL 6 WSW GREENFIELD 41.29N 94.57W
04/24/2009 E1.25 INCH ADAIR IA TRAINED SPOTTER
QUARTER TO HALF DOLLAR SIZE HAIL.
0835 PM HAIL 5 SSE FONTANELLE 41.23N 94.53W
04/24/2009 E0.75 INCH ADAIR IA TRAINED SPOTTER
PEA TO PENNY HAIL.
0839 PM HAIL 3 NE ORIENT 41.23N 94.38W
04/24/2009 E1.00 INCH ADAIR IA EMERGENCY MNGR
0839 PM HAIL 3 WNW ORIENT 41.21N 94.47W
04/24/2009 E1.00 INCH ADAIR IA TRAINED SPOTTER
0903 PM HAIL 2 SE ORIENT 41.19N 94.39W
04/24/2009 E1.00 INCH ADAIR IA TRAINED SPOTTER
0906 PM HAIL 2 SE ORIENT 41.19N 94.39W
04/24/2009 E1.75 INCH ADAIR IA TRAINED SPOTTER
1047 PM HAIL 3 W AFTON 41.03N 94.25W
04/24/2009 E1.00 INCH UNION IA LAW ENFORCEMENT
1047 PM HAIL 3 W AFTON 41.03N 94.25W
04/24/2009 E1.00 INCH UNION IA LAW ENFORCEMENT
1049 PM TSTM WND GST 3 NE CRESTON AIRPORT 41.05N 94.31W
04/24/2009 M60.00 MPH UNION IA MESONET
RWIS SENSOR
&&
BMOYERThe Des Moines radar (KDMX), 22 km away, was scanning. The volume nearest the first event began at 11:28 UTC.
21 heavy rain, 18 flash flood, 8 thunderstorm wind, 4 flood, 1 tornado, 1 lightning. Local standard time, as filed.
Total from Saturday through Monday morning, 1.24 inches from Sunday night into Monday morning.
Weekend total.
Weekend total.
Weekend total of 7.40 inches.
Weekend total of 4.11 inches.
From the Des Moines Register. Total from Saturday night through Monday morning.
Weekend total.
Total since 0600 CST Sunday.
Total since 0600 CST Sunday, 4.03 inches.
Rainfall of 4.66 inches in past 25 hours.
Rainfall of 3.40 inches in past 24 hours.
Rainfall of 3.51 inches in past 24 hours.
Rainfall of 3.62 inches in past 24 hours.
Rainfall of 3.18 inches in past 24 hours.
Weekend total of 5 inches, 4.25 in past 24 hours.
Weekend total of 4.02 inches, with 3.47 in the past 24 hours.
Weekend total of 3.26 inches, with 2.86 inches in past 24 hours.
Five inches of rain fell since 0800 CST with water coming into the basement on all 4 sides.
Rainfall of 7 inches in past 24 hours.
Reports of 18 to 24 inches of flowing water through the intersection.
Water was over Highway 25 just south of Guthrie Center.
Water reported over Highway 25 in Guthrie Center.
Water reported over 195th Street.
Water reported over the road at 140th St and Delta Ave.
Water reported over White Pole Rd.
Iowa Highway 25 was closed due to water over the road.
Water was over the road in several places between Jamaica and Yale.
A roof was blown off of a barn near 215th St and 190th Ave. Numerous tree limbs were down.
Brief tornado about 1.25 miles long. Track about 30 miles wide. The EF0 rating was based on pictures and coordination with the Emergency Manager.
Outbuilding damage 2.19 miles south of Beaman.
Water was reported as waist deep on Linn St and Church St in Marshalltown.
Chicken Creek had risen out of its banks.
One and one half foot diameter trees downed.
Flash flooding resulted in the collapse of a culvert at Frontier Rd and 292nd St.
A 30 foot section of a trailer was blown by strong winds.
A large tree was blown into a power pole and another power pole was downed.
Total of 4.30 inches since Saturday afternoon.
Flooding has popped up manhole covers on Upton Ave near Ansborough Ave.
Water was reported over roads in the county.
Water was reported over the roads.
Water was over the northbound lanes of Iowa Highway 14.
Water over Garwin Rd. near the intersection with Iowa Highway 14.
Pleasant Creek was was out of its banks at Raymond Rd and E. Donald and rising. Four inches of rain fell today on top of the 1 inch Saturday.
Flooding was reported along English Creek between 80th and 90th Ave. on Utah St., and between Utah St. and Vermont St. on 78th Ave.
Flooding was reported along English Creek on 108th Place between Pierce and Perry streets, and on 130th Place between Oregon St. and Highway 14.
Flooding was reported along 200th between Beardsley and County Line Road, and on County Line Road between 190th and 200th.
Highway 65 at Highway 34 was closed in both directions near Lucas because of flooding.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2009Every state in 2009This day in weather historyThe tornado archive for Iowa, 2009Warnings in Iowa, April 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: 156256, 156255, 156262, 156263, 156271, 156272, 156257, 156254, 156258, 156259, 156260, 156267, 156268, 156269, 156270, 156264, 156265, 156266, 156039, 156273, 156015, 156016, 156017, 156018, 156019, 156020, 156252, 156023, 156029, 156494, 156030, 156054, 156055, 156033, 156028, 156034, 156035, 156036, 156037, 156261, and more.