S. The system moved very slowly and produced a large rain shield.
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.
A strong low pressure system lifted northeast out of the southwest U.S. The system moved very slowly and produced a large rain shield. Moderate to heavy rain fell over an extended period of time over parts of eastern Iowa. Rainfall totals were in the 2 to 3 inch range over a 36 hour period in an arc extending from west of Ottumwa through the Waterloo area. Spot reports of around 4 inches were received. The ground was already saturated before the event began. As a result, numerous county roads were over topped by water and a few washouts occurred in Black Hawk County.
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 18, 5:45 AM CST, 2 hours 30 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DES MOINES IA 645 AM CDT FRI APR 18 2008 ...UPDATED FOR AVIATION DISCUSSION... .SHORT TERM...TODAY SHORT TERM ISSUE FOCUS SQUARELY ON SYSTEM PASSING THOUGH THE STATE TODAY. SFC LOW PRESSURE CURRENTLY NEAR KMCI AND MOVING GRADUALLY NORTHEAST. HAVE HAD WIDESPREAD MODERATE TO HEAVY RAINS ACROSS PORTIONS OF THE SOUTHERN CWA WHERE ONE TO ONE AND THREE QUARTERS OF AN INCH HAS ALREADY FALLEN. RIVERS IN THE AREA HAVE RISEN RAPIDLY IN RESPONSE AND EXPECT THIS TO PERSIST INTO TODAY. APPEARS TRAIN OF SHOWERS AND ISOLD CONVECTION WL CONTINUE ACRS THE SOUTHEAST THROUGH MID MORNING BEFORE SOME BREAK. WL ALSO WATCH FOR BRIEF PERIODS OF HEAVIER DOWNPOURS WITH ANY POSSIBLE CONVECTION AS FLASH FLOODING WOULD BE EASY TO PRODUCE GIVEN THE MOIST CONDITIONS. BREAK LATER THIS MORNING AND EARLY AFTERNOON MAY BE SHORT IN DURATION AS MODELS SUGGESTING THAT SOME DEFORMATION PCPN WL SLIDE BACK OVER THOSE AREAS WITH ADDITIONAL RAINFALL. FARTHER NORTHWEST...EXPECT DEFORMATION PCPN TO DEVELOP OVER THE NEXT FEW HOURS WITH A DECENT BAND OF PCPN BY MID MORNING. THIS AREA WL GRADUALLY SLIDE EAST NORTHEAST DURING THE DAY AS THE UPPER LOW AND ASSOCIATED FORCING PUSH INTO THE LOWER MISSOURI AND MID MISSISSIPPI RIVER VALLEYS. SEE NO REASON TO CANCEL WATCH AT THIS POINT AND WL CONTINUE THROUGH 6 PM THIS EVENING. GIVEN EXTENSIVE CLOUDINESS AND PCPN...HAVE UNDERCUT GUIDANCE IN MOST LOCATIONS. EXCEPTION MAY BE IN THE SOUTHEAST WHERE WARM SECTOR REMAINS IN PLACE. && LONG TERM...TONIGHT THROUGH THURSDAY THE STORM SYSTEM AFFECTING IOWA TODAY WILL BE SLOW TO DEPART...DRIFTING INTO WESTERN ILLINOIS LATER TONIGHT AND AROUND NORTHERN INDIANA SATURDAY. THIS WILL LEAD TO DIMINISHING RAIN CHANCES IN THE WEST LATE TONIGHT...HOWEVER POPS WILL REMAIN HIGH IN THE EAST THROUGH SATURDAY. AS THE LOW FINALLY EXITS EASTWARD SATURDAY NIGHT SOME RIDGING WILL BRING A BRIEF PERIOD OF DRY AND QUIET WEATHER SUNDAY AND SUNDAY NIGHT. CONCURRENTLY A LARGE MID-LEVEL CYCLONE WILL SPIN UP OVER WESTERN MONTANA...WITH A SURFACE TROUGH MOVING OVER THE GREAT PLAINS AND APPROACHING WESTERN IOWA BY MONDAY MORNING. IT IS BEYOND THIS POINT THAT LONG-RANGE FORECAST MODELS DIFFER IN THEIR SOLUTIONS FOR RAINFALL AND SURFACE FIELDS...AS BOTH THE GFS AND ECMWF MAINTAIN THE MID-LEVEL TROUGH OVER THE NORTHERN ROCKIES THROUGH THE END OF THE WEEK. BY THUS PLACING OUR AREA BENEATH PERSISTENT SOUTHWESTERLY 500 MB FLOW...THE MODELS ARE SPINNING UP SURFACE LOW PRESSURE SYSTEMS WHICH MOVE RAPIDLY NORTHEASTWARD THROUGH THE MIDWEST. THE DEVELOPMENT AND TIMING OF SUCH SYSTEMS IS VERY DIFFICULT TO PREDICT...AND THIS IS LEADING TO A LOT OF VARIATION IN SURFACE SOLUTIONS FROM MODEL TO MODEL AND FROM RUN TO RUN. THERE IS SOME GENERAL AGREEMENT IN PARTICULARLY HIGH RAIN CHANCES MONDAY NIGHT AND TUESDAY MORNING...AND AGAIN TOWARD THE END OF THE FORECAST PERIOD. WITH GOOD MID-LEVEL ENERGY AT LEAST ISOLATED THUNDERSTORMS ARE LIKELY DURING THE PERIODS OF HIGHER RAIN CHANCES. && .AVIATION...18/12Z CEILINGS WL REMAIN IFR ACRS MUCH OF IA TODAY WITH THE EXCEPTION OF THE FAR EAST WHERE VFR AND MVFR CONDITIONS WL PREVAIL. WNDS WL BE VRBL ACRS THE STATE TODAY AS SFC LOW PRESSURE MOVES ACRS SOUTH CENTRAL INTO EAST CENTRAL IOWA. WIDESPREAD DRIZZLE AND SHRA ACTIVITY IS EXPECTED AS THE LOW PULLS THROUGH THE STATE. THE IFR CONDITIONS WL CONTINUE OVERNIGHT AS LOW LEVEL MOISTURE REMAINS PLENTIFUL. && .DMX WATCHES/WARNINGS/ADVISORIES...FLOOD WATCH GENERALLY ALONG AND SE OF BLACK HAWK-POLK-DECATUR COUNTIES TODAY. && LONG TERM...LEE SHORT TERM/AVIATION...COGIL
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE DES MOINES IA 512 AM CDT FRI APR 18 2008 IAZ038-039-049-050-060>062-073>075-083>086-094>097-191015- GRUNDY-BLACK HAWK-MARSHALL-TAMA-POLK-JASPER-POWESHIEK-WARREN- MARION-MAHASKA-CLARKE-LUCAS-MONROE-WAPELLO-DECATUR-WAYNE- APPANOOSE-DAVIS- 512 AM CDT FRI APR 18 2008 THIS HAZARDOUS WEATHER OUTLOOK IS FOR A PORTION OF CENTRAL IOWA MAINLY SOUTHEAST OF A WATERLOO TO CARROLL LINE. .DAY ONE...TODAY AND TONIGHT ISOLATED NON SEVERE THUNDERSTORMS ARE POSSIBLE TODAY. A FLOOD WATCH REMAINS IN EFFECT TODAY FOR PERIODS OF MODERATE TO LOCALLY HEAVY RAINFALL RESULTING IN PONDING WATER IN FIELDS AND RISES ON AREA STREAMS AND RIVERS AND POSSIBLE RIVER FLOODING. FLOOD WARNINGS HAVE BEEN ISSUED FOR THE SOUTH SKUNK...SOUTH FORK CHARITON...AND CHARITON RIVERS. PLEASE REFER TO THE NATIONAL WEATHER SERVICE WEBSITE AT WEATHER.GOV/DESMOINES FOR FURTHER DETAILS. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY WHILE RAIN CHANCES WILL DIMINISH SATURDAY...THERE WILL STILL BE RESIDUAL RISES IN AREA STREAMS AND RIVERS AND POSSIBLE RIVER FLOODING THROUGH THE WEEKEND. ADDITIONAL CHANCES FOR THUNDERSTORMS WILL ARRIVE SUNDAY NIGHT THROUGH TUESDAY. THERE IS THE POTENTIAL FOR STORMS TO BE STRONG TO SEVERE. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED HOWEVER RAINFALL REPORTS AND ANY REPORTS OF FLOODING WOULD BE GREATLY APPRECIATED. IAZ004>007-015>017-023>028-033>037-044>048-057>059-070>072-081- 082-092-093-191015- EMMET-KOSSUTH-WINNEBAGO-WORTH-PALO ALTO-HANCOCK-CERRO GORDO- POCAHONTAS-HUMBOLDT-WRIGHT-FRANKLIN-BUTLER-BREMER-SAC-CALHOUN- WEBSTER-HAMILTON-HARDIN-CRAWFORD-CARROLL-GREENE-BOONE-STORY- AUDUBON-GUTHRIE-DALLAS-CASS-ADAIR-MADISON-ADAMS-UNION-TAYLOR- RINGGOLD- 512 AM CDT FRI APR 18 2008 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL IOWA. .DAY ONE...TODAY AND TONIGHT ISOLATED NON SEVERE THUNDERSTORMS ARE POSSIBLE TODAY. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY ISOLATED NON SEVERE THUNDERSTORMS WILL CONTINUE THROUGH FRIDAY. ADDITIONAL CHANCES FOR THUNDERSTORMS WILL ARRIVE SUNDAY NIGHT THROUGH TUESDAY. THERE IS THE POTENTIAL FOR STORMS TO BE STRONG TO SEVERE. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED HOWEVER RAINFALL REPORTS WOULD BE GREATLY APPRECIATED. LEE
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
831 AM CDT FRI APR 18 2008
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0530 PM LIGHTNING 2 ENE ELLSTON 40.85N 94.06W
04/17/2008 RINGGOLD IA TRAINED SPOTTER
LIGHTNING STARTED HOUSE FIRE AT SUN VALLEY LAKE. TIME
APPROXIMATE.
&&
SMALLThe national radar mosaic for the moment the first event began.
9 flood. Local standard time, as filed.
Water was reported over 275th between Jewell and Kaplar Avenues.
The first washout was reported on Hess Road.
Water was reported over Highway 8 on the east edge of Traer.
The Des Moines River was out of its banks and flowing into nearby fields near the Chillicothe bridge. More water was in the fields toward Ottumwa.
Hess road remained closed between Reinbeck Rd and Eagle Rd.
Ranchero Road was closed between Sergeant Rd and DeWitt Rd.
Black Hawk Rd was closed just east of Cedar Heights Dr.
Butler Rd was closed just south of Beaver Valley Rd.
Bennington Rd. was closed between Raymond Rd. and Crane Creek Rd.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2008Every state in 2008This day in weather historyWarnings in Iowa, April 2008
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: 81844, 81847, 81848, 81849, 81850, 81851, 81852, 81853, 81854.