216 flood insurance claims·$3.2M paid·6 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 Cerro Gordo 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.
Over the last 30 years, long-duration river flooding mixed with frequent flash flooding from summer thunderstorms defines the flood character of Cerro Gordo County, recorded through 50 flood events and 32 flash flood events in the NOAA Storm Events Database.
Historical events illustrate these multi-season risks. In February 2023, over an inch of rain falling on a two-to-four-inch snowpack and frozen ground caused runoff that sent the Winnebago River at Mason City into minor river flooding. Similarly, in March 2019, heavy rain and warm temperatures melted a winter snowpack over frozen ground, generating rapid runoff and widespread flooding. Summer weather also brings severe impacts, as demonstrated by heavy rainfall on saturated soils that caused flash flooding and significant river flooding in June 2024.
National Flood Insurance Program records show that property owners in high-risk Zone A face the heaviest impacts, accounting for 150 claims with an average payout of $24,077 and an average recorded water depth of 27 inches. Residents located near rivers and within Zone A, as well as those in shaded and unshaded Zone X areas, should pay the closest attention to flood preparedness, as claims in unshaded Zone X recorded an average water depth of 29 inches and an average payout of $27,817.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
11% of Cerro Gordo County’s flood insurance claims were on properties rated outside FEMA’s high-risk zones.
168 NFIP claims with a recorded rated flood zone, 1978 to date. The zone is the one FEMA used to rate that policy, which may not match today’s map. Source: OpenFEMA NFIP claims.
In flood insurance claims here that reported a flood depth, the average was 22 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 2008, with 89 claims and $2.6M paid, the year of Severe Storms, Tornadoes, 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.
72 NOAA storm reports from Cerro Gordo County describe what happened, in the words of the forecasters who covered it. Read the Iowa flood stories →
15 federal disaster declarations since 1965, 6 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Severe Storms, Tornadoes, Straight-line Winds, And Flooding | Jun 6, 2018 |
| Severe Storms And Flooding | Sep 21, 2016 |
| Severe Storms, Tornadoes, And Flooding | May 25, 2008 |
| Hurricane Katrina Evacuation | Aug 29, 2005 |
| Severe Storms, Tornadoes, And Flooding | May 19, 2004 |
| Severe Storms And Flooding | Jul 2, 1999 |
| Severe Storms, Tornadoes And Flooding | Jun 13, 1998 |
| Severe Storms & Flooding | Apr 13, 1993 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
82 since 1996: 32 flash floods and 50 river or area floods.
| Event | Date | Damage |
|---|---|---|
| Flood | Jun 22, 2024 | — |
| Flood | Feb 27, 2023 | — |
| Flood | Apr 13, 2022 | — |
| Flood | Mar 19, 2019 | — |
| Flood | Mar 15, 2019 | — |
| Flood | Mar 14, 2019 | $200,000 |
| Flood | Mar 14, 2019 | — |
| Flood | Sep 20, 2018 | $100,000 |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Flood · Jun 22, 2024. Heavy rain fell over portions of northern Iowa, especially northwestern Iowa and bordering states later on June 20 through early on June 21. This rainfall caused flash flooding in portions of northwest Iowa and also aided in saturating the soil. As another round of heavy rain fell later on June 21 into the night and morning of June 22, this rainfall led to renewed flash flooding. This rainfall made its way into st…
Flood · Feb 27, 2023. A large and unseasonably warm system brought showers and thunderstorms to the state. Over an inch of rain fell across much of Iowa. In northern Iowa, this was on top of a snowpack of two to four inches. The quick rain on top of frozen group resulted in runoff sufficient to send the Winnebago River at Mason City into minor river flooding. The river exceeded minor flood stage and quickly crested the morning of Febru…
Flood · Apr 13, 2022. Initial storms developed within the warm sector of a surface low that tracked northwest of the area, followed by a strong cold front with associated dry line that produced a quasi-linear (QLCS) storm mode later in the evening. Several tornadoes occurred across western into northern Iowa. Initially the tornadoes were associated with supercell storms, however later storms produced QLCS tornadoes as it raced east no…
Flood · Mar 19, 2019. Much of the river flooding occurred across Iowa through the middle of the month when the area lost its snowpack and received heavy rainfall. A secondary period of flood was observed on the Winnebago River at Mason City from snowmelt and heavy rain that fell across southern Minnesota toward the latter half of the month. Other rivers in northern Iowa remain in flood through the end of March and into April from the m…
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 Cerro Gordo 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.