Enter any address in Clarke County, Iowa to see its FEMA flood zone
Flash flooding from intense rainfall events is a primary flood concern in Clarke County. Between 2000 and 2020, NOAA Storm Events data recorded 42 flood events and 21 flash flood events in the county. For example, heavy rainfall on August 7, 2025, resulted in several inches of rain across parts of Clarke County. Earlier, on March 12, 2019, an ice jam on the Des Moines River caused flash flooding in Ottumwa, with water levels rising rapidly and flooding several vehicles and campers.
Residents in areas prone to flash flooding, particularly those located in lower elevations or downstream from heavy rainfall, should be aware of these risks. Homeowners in zones with higher flood risk, as identified by FEMA, should pay close attention to flood advisories and consider flood insurance.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
55 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Clarke County, Iowa has recorded 63 flood-related events since 1996 according to NOAA's Storm Events Database, including 21 flash floods and 42 river or area floods. The county has received 16 federal disaster declarations, 6 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1969–2024)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| Severe Storms And Tornadoes | Tornado | Apr 26, 2024 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Severe Storms, Tornadoes, Straight-line Winds, And Flooding | Severe Storm | Jun 3, 2014 |
| Severe Storms, Flooding, And Tornadoes | Severe Storm | Jun 1, 2010 |
| Severe Storms, Tornadoes, And Flooding | Severe Storm | May 25, 2008 |
| Severe Winter Storm | Severe Ice Storm | Dec 10, 2007 |
| Severe Storms, Flooding, And Tornadoes | Severe Storm | May 5, 2007 |
| Hurricane Katrina Evacuation | Hurricane | Aug 29, 2005 |
| Severe Storms, Tornadoes And Flooding | Flood | Jun 13, 1998 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flash Flood | Aug 7, 2025 | 0.00K |
| Flood | Mar 12, 2019 | 200.00K |
| Flash Flood | Sep 24, 2016 | 20.00K |
| Flood | Jun 25, 2015 | 250.00K |
| Flash Flood | Jul 11, 2015 | 100.00K |
| Flood | Aug 23, 2014 | 100.00K |
| Flash Flood | Aug 23, 2014 | 250.00K |
| Flash Flood | May 11, 2014 | 25.00K |
| Flood | Sep 10, 2014 | 100.00K |
| Flash Flood | Sep 10, 2014 | 100.00K |
Flash Flood — Aug 7, 2025
Iowa was on the edge of a deep thermal ridge. Several weak embedded waves moved across, aiding in thunderstorms development as the interacted with the low level jet through the early morning. These early morning storms did remain sub severe, but produced heavy rain that continued through midday. Training storms across southern Iowa result in an area of five to seven plus inches of rain, but no ...
Flood — Mar 12, 2019
Early reports starting on the 9th are in this entry, with several later reports starting on the 13th in Part II. ||Additionally the combination of heavy snowpack and heavy rainfall absorbed into the snow partially collapsed a horse barn roof in rural Adair County near Greenfield. ||An ice jam occurred in Ottumwa on the Des Moines River causing flash flooding were water rapidly rose several feet...
Flash Flood — Sep 24, 2016
Leading up to this event, a low pressure system was slowly working its way northeast through the Dakotas and into southern Canada. The associated fronts made their presence felt within Iowa on the 24th and 25th. The warm front worked its way up through the state on the 24th with little consequence, followed by the cold front and leading storms overnight the 24th into the 25th. While no damag...
Flood — Jun 25, 2015
A slowly northward moving boundary/warm front was draped across the area throughout the day. By the evening vigorous storms fired up just north of the boundary and continued as the low level jet began to pick up. Numerous reports of large hail and damaging winds were reported. Fairly quickly after sunset, storms transitioned away from multi-cellular severe to training heavy rain producers ove...
Flash Flood — Jul 11, 2015
A warm front pushed into southern Iowa from Missouri, bringing with it storms and heavy rainfall. The front progressed slowly, aiding in keeping the rain over the same areas for long periods of time. By the end of the day, a number of areas across the south reported 4+ inches of rain with the highest totals around 5.5-5.75 near Lorimor, Rathbun, Derby, and Humeston. Localized flash flooding ...
Source: NOAA National Weather Service Storm Events Database.
FEMA assigns flood zone designations to areas in Clarke County, Iowa:
AE High Risk — 1% annual chance of flooding. Insurance required.
VE Very High Risk — Coastal flooding with wave action.
X (Shaded) Moderate Risk — 500-year floodplain.
X Low Risk — Outside major floodplains.
Properties in Clarke County, Iowa that are in FEMA-designated Special Flood Hazard Areas (zones A and V) with federally backed mortgages are required to carry flood insurance.
Even outside high-risk zones, flood insurance is recommended. From 2014 to 2024, nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area.
Visit FloodSmart.gov to find an agent and get a quote.