Enter any address in Story County, Iowa to see its FEMA flood zone
Flood and flash flood events are the primary weather hazards in Story County, Iowa. Between 2000 and 2023, NOAA Storm Events data recorded 78 flood events and 64 flash flood events. Recent examples include widespread flash flooding across northern and central Iowa on May 21, 2024, following multiple rounds of thunderstorms that dropped 2 to 4 inches of rain. On June 15, 2022, heavy rainfall of 4 inches or more in and around Story County caused the South Skunk River in Ames to briefly reach flood stage.
National Flood Insurance Program (NFIP) claims data indicates that properties in Zone A, which typically represent areas of moderate to major flood hazard, have experienced the highest number of claims (157) with an average payout of $41,513 and an average water depth of 2.0 feet. Properties in Zone X_SHADED and Zone X_UNSHADED also show significant claim activity and payouts, with Zone X_UNSHADED having a notably high average payout of $115,899 and an average water depth of 3.2 feet. Homeowners in areas designated as Zone A, as well as those in Zone X_SHADED and Zone X_UNSHADED, should pay close attention to flood risk information.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
130 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Story County, Iowa has recorded 142 flood-related events since 1996 according to NOAA's Storm Events Database, including 64 flash floods and 78 river or area floods. The county has received 21 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, Tornadoes, And Flooding | Severe Storm | May 20, 2024 |
| Severe Storms | Severe Storm | Aug 10, 2020 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Severe Storms, Tornadoes, Straight-line Winds, And Flooding | Severe Storm | Jun 6, 2018 |
| Severe Storms, Tornadoes, And Flooding | Severe Storm | May 19, 2013 |
| Severe Storms, Straight-line Winds, And Flooding | Severe Storm | Jul 9, 2011 |
| Severe Storms, Flooding, And Tornadoes | Severe Storm | Jun 1, 2010 |
| Severe Winter Storm | Severe Storm | Jan 19, 2010 |
| Severe Storms, Tornadoes, And Flooding | Severe Storm | May 25, 2008 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flood | May 21, 2024 | 0.00K |
| Flash Flood | Apr 22, 2022 | 0.00K |
| Flood | Jun 15, 2022 | 0.00K |
| Flash Flood | Jul 14, 2021 | 0.00K |
| Flood | May 24, 2019 | 0.00K |
| Flood | May 24, 2019 | 5.00K |
| Flood | May 24, 2019 | 10.00K |
| Flood | May 23, 2019 | 0.00K |
| Flash Flood | Jun 21, 2019 | 0.00K |
| Flood | Mar 15, 2019 | 200.00K |
Flood — May 21, 2024
PLEASE NOTE, for tornadoes, please see separate Storm Data entry for May 21st. ||Multiple rounds of thunderstorms brought torrential rainfall, damaging winds, hail and destructive tornadoes to the state. These thunderstorms were the result of a low pressure system which lifted north into the area on the night of May 20th, 2024, producing slow moving storms that dropped 2 to 4 inches of rainfall...
Flash Flood — Apr 22, 2022
A warm front moved across the area late on the evening of April 21 into April 22. While thunderstorms remained below severe criteria, deep saturation and precipitable water values over 1.5 inches allowed for a band of heavier precipitation to set up over a narrow corridor in central Iowa. Several locations received over 3 inches of rain and a few areas saw flash flooding within towns, resulting...
Flood — Jun 15, 2022
Storms from the 14th into the 15th resulted in severe weather and heavy rainfall. A number of stations and reports of 4 inches or greater rainfall were received in and around Story County. As a result, the South Skunk River in Ames at US 30 briefly went into flood stage on the 15th of June.
Flash Flood — Jul 14, 2021
A surface low pressure system was centered over Kansas and Nebraska with attendant warm front draped across north central Iowa. This was bisected by an outflow boundary from morning convection across western Iowa. As morning activity exited the are the atmosphere quickly recovered steep low and mid level lapse rates exceeded 8 C/km with 0-6 km shear over 40 knots. Near the remnant outflow bound...
Flood — May 24, 2019
The setup over Iowa was primed for a heavy rainfall event for a few reasons, including persistent SW 500 mb flow, a strong and SW oriented 850 mb jet, strong low level moisture transport, and elevated CAPE around 1000-2000 J/kg. Precipitable water values, given the strong moisture transport into the area, rose into the neighborhood of 1.7 inches throughout the event as well. While effective bul...
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 Story 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 Story 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.