Enter any address in O'Brien County, Iowa to see its FEMA flood zone
Flash flooding from thunderstorms is a significant concern in O'Brien County. Between 1996 and 2024, NOAA Storm Events data recorded 54 flood events and 19 flash flood events in the county. For example, heavy rainfall associated with thunderstorms caused localized flash flooding in northwest Iowa in late July 2025. In June 2024, excessive rainfall over two days led to significant accumulations, with some areas receiving 8 to 16 inches.
National Flood Insurance Program (NFIP) claims data indicates that while Zone X areas have seen more claims, Zone X_Unshaded areas have experienced deeper water, with an average of 3.0 feet. Homeowners in areas prone to flash flooding, particularly those near areas that receive heavy rainfall or in lower-lying zones, should pay close attention to flood risk.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
23 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
O'Brien County, Iowa has recorded 73 flood-related events since 1996 according to NOAA's Storm Events Database, including 19 flash floods and 54 river or area floods. The county has received 15 federal disaster declarations, 4 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1965–2024)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| Severe Storms, Flooding, Straight-line Winds, And Tornadoes | Severe Storm | Jun 16, 2024 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Severe Storms And Flooding | Flood | Mar 12, 2019 |
| Severe Storms, Tornadoes, Straight-line Winds, And Flooding | Severe Storm | Jun 6, 2018 |
| Severe Storms, Tornadoes, And Flooding | Severe Storm | May 19, 2013 |
| Severe Winter Storm | Severe Storm | Apr 9, 2013 |
| Severe Storms, Flooding, And Tornadoes | Severe Storm | Jun 1, 2010 |
| Severe Winter Storms And Snowstorm | Severe Storm | Dec 23, 2009 |
| Snow | Snowstorm | Feb 28, 2007 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flash Flood | Jul 30, 2025 | 0.00K |
| Flash Flood | Jul 28, 2025 | 0.00K |
| Flood | May 31, 2024 | 0.00K |
| Flood | May 22, 2024 | 0.00K |
| Flash Flood | Jun 21, 2024 | 0.00K |
| Flood | Jun 21, 2024 | 0.00K |
| Flood | Jun 21, 2024 | 2.25M |
| Flood | May 2, 2024 | 0.00K |
| Flood | Jul 1, 2024 | 0.00K |
| Flood | Aug 5, 2023 | 0.00K |
Flash Flood — Jul 30, 2025
Thunderstorms erupted within a very moist and unstable environment across central South Dakota during the afternoon of July 29 in response to an approaching upper level short-wave from Colorado. These thunderstorms quickly grew upscale into a line, producing 55 to 75 mph wind gusts across southeast South Dakota and extreme northeast Nebraska, resulting in isolated tree damage. In addition, prol...
Flash Flood — Jul 28, 2025
Thunderstorms rapidly developed across northeast South Dakota into west central Minnesota during the early evening of July 27 within a volatile environment (MUCAPE 5000-6000 J/Kg) ahead of a southward moving surface boundary. These thunderstorms expanded into a mesoscale convective system and dropped south across the region through the remainder of the evening into the early overnight hours on ...
Flood — May 31, 2024
Scattered thunderstorms during the afternoon and evening hours produced pockets of heavy rainfall and very efficient rainfall rates. This resulted in localized flash flooding reports across far southeast South Dakota, far northeast Nebraska, and northwest Iowa. Even after the heaviest rainfall rates had ended, a stripe of prolonged moderate rainfall resulted in excessive ponding and some minor ...
Flood — May 22, 2024
Another wet period during the mid to later part of May drove portions of the upper and middle Little Sioux Basin back above flood stage after only briefly falling below flood stage just a handful of days early.
Flash Flood — Jun 21, 2024
More isolated afternoon and early evening storms erupted just north of a frontal boundary across northeast Nebraska and western Iowa, which produced up to quarter size hail and damaging wind gusts of 60 to 75 mph. Storms became more widespread during the evening given a mid-level impulse and increase in the low-level jet across the frontal boundary. The rain regenerated in many of the same area...
Source: NOAA National Weather Service Storm Events Database.
Source: OpenFEMA NFIP Individual Claims (2.25M records analyzed).
FEMA assigns flood zone designations to areas in O'Brien 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 O'Brien 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.