4 flood insurance claims·$144,474 paid·4 federal flood & hurricane disasters
Share of the whole county outline, rivers and lakes included; parts FEMA hasn’t mapped count as zero.
Shaded areas are FEMA’s mapped flood hazard zones in and around O'Brien County, Iowa. Zoomed out they are simplified; at street level the map switches to FEMA’s exact layer. Tap anywhere to check that spot, or search an address above.
O'Brien County experiences a flood risk profile dominated by standard floods and flash floods from summer thunderstorms. Over the last 30 years, the NOAA Storm Events Database recorded 54 flood events and 19 flash flood events.
Recent events illustrate these severe weather patterns. In June 2024, isolated afternoon and evening storms along a frontal boundary regenerated over consecutive nights, bringing two-day rainfall totals as high as 8 to 16 inches and causing localized flash flooding. Later, in July 2025, a mesoscale convective system dropped south across the region, while a separate event on July 30, 2025, involved thunderstorms erupting in a moist environment that produced prolonged heavy rain and localized flash flooding across northwest Iowa.
Historical National Flood Insurance Program records indicate claims in lower-risk areas, including 3 claims in Zone X with an average payout of $47,792 and an average recorded water depth of 1 inch, and 1 claim in Zone X_UNSHADED with an average payout of $1,099 and an average recorded water depth of 3 inches. Homeowners and real estate agents in these mapped zones should pay close attention to drainage and localized heavy rainfall accumulation.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
In flood insurance claims here that reported a flood depth, the average was 2 inches.
Drawn to scale against an 80-inch door. Even a few inches soaks flooring, the bottom of the drywall and anything plugged in near the floor.
Average of the depths reported on claims (zero and implausible values left out); FEMA’s record doesn’t say exactly where each depth was measured. Source: OpenFEMA NFIP claims.
The worst year was 2018, with 2 claims and $21,435 paid, the year of Severe Storms, Tornadoes, Straight-line Winds, and Flooding.
Bar height is scaled by square root so ordinary years stay visible next to the worst one. NFIP claims by year of loss. Source: OpenFEMA.
23 NOAA storm reports from O'Brien County describe what happened, in the words of the forecasters who covered it. Read the Iowa flood stories →
15 federal disaster declarations since 1965, 4 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Severe Storms, Flooding, Straight-line Winds, And Tornadoes | Jun 16, 2024 |
| Severe Storms And Flooding | Mar 12, 2019 |
| Severe Storms, Tornadoes, Straight-line Winds, And Flooding | Jun 6, 2018 |
| Severe Storms, Tornadoes, And Flooding | May 19, 2013 |
| Severe Winter Storm | Apr 9, 2013 |
| Severe Storms, Flooding, And Tornadoes | Jun 1, 2010 |
| Severe Winter Storms And Snowstorm | Dec 23, 2009 |
| Snow | Feb 28, 2007 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
73 since 1996: 19 flash floods and 54 river or area floods.
| Event | Date | Damage |
|---|---|---|
| Flash Flood | Jul 30, 2025 | — |
| Flash Flood | Jul 28, 2025 | — |
| Flood | May 31, 2024 | — |
| Flood | May 22, 2024 | — |
| Flash Flood | Jun 21, 2024 | — |
| Flood | Jun 21, 2024 | — |
| Flood | Jun 21, 2024 | $2.2M |
| Flood | May 2, 2024 | — |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
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, prolonged heavy rain res…
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 July 28. Most report…
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 flooding of rural ro…
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.
National Weather Service narratives, lightly trimmed. Source: NOAA Storm Events Database.
Every colour on the map above is a place on this drawing: where the ground sits relative to the flood FEMA plans for.
If a building in O'Brien County is in a high-risk zone (A or V) and its mortgage comes from a federally regulated or insured lender, or is federally backed, flood insurance is required.
Outside those zones it is optional, and often worth having: from 2014 to 2024 nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area. Since Risk Rating 2.0, NFIP premiums are set for each building, so the only reliable price is a quote: FloodSmart.gov or a local agent.