Enter any address in Grundy County, Iowa to see its FEMA flood zone
Flash flooding from heavy rainfall events is a significant concern in Grundy County, IA. Over the past 30 years, NOAA Storm Events data shows 36 flood events and 20 flash flood events. For instance, in May 2024, multiple rounds of thunderstorms brought torrential rainfall, leading to flash flooding across portions of northern and central Iowa. Similarly, in June 2020, localized heavy rain resulted in flooding overnight following severe thunderstorms.
National Flood Insurance Program (NFIP) claims data indicates that properties in Zone A have experienced an average of 3.4 feet of water depth with an average payout of $2,942. Notably, a claim in Zone X, which typically represents areas of minimal to moderate flood hazard, reported an average water depth of 12.0 feet and an average payout of $7,361. Homeowners in areas designated as Zone A, as well as those in Zone X who have experienced significant water depth, should pay close attention to flood risk.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
50 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Grundy County, Iowa has recorded 56 flood-related events since 1996 according to NOAA's Storm Events Database, including 20 flash floods and 36 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 (1969–2020)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| 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 26, 2014 |
| Severe Storms, Tornadoes, And Flooding | Severe Storm | Jun 21, 2013 |
| Severe Storms, Tornadoes, And Flooding | Severe Storm | May 19, 2013 |
| Severe Storms, Tornadoes, And Flooding | Severe Storm | May 25, 2008 |
| Severe Winter Storms | Severe Storm | Feb 23, 2007 |
| Hurricane Katrina Evacuation | Hurricane | Aug 29, 2005 |
| Severe Storms, Tornadoes, And Flooding | Severe Storm | May 19, 2004 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flash Flood | May 21, 2024 | 0.00K |
| Flood | Jun 22, 2020 | 0.00K |
| Flood | Mar 14, 2019 | 100.00K |
| Flood | Oct 1, 2018 | 0.00K |
| Flood | Jul 1, 2018 | 100.00K |
| Flood | Aug 28, 2015 | 100.00K |
| Flash Flood | Aug 28, 2015 | 10.00K |
| Flash Flood | Aug 28, 2015 | 100.00K |
| Flood | Dec 14, 2015 | 100.00K |
| Flash Flood | Jun 30, 2014 | 100.00K |
Flash 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...
Flood — Jun 22, 2020
A surface low to the northwest of Iowa allowed for convection to develop in the warm sector and along the surface boundary as it pushed across northern Iowa through the afternoon and evening of the 21st. These storms caused damaging winds and large hail across northern and central Iowa. Localized areas received heavy rain that resulted in flooding overnight. Another shortwave embedded within th...
Flood — Mar 14, 2019
Reports from the 13h through the 19th in this entry. ||A relatively deep and widespread snowpack existed across the region during early to mid March. Many areas in central and northern Iowa had around a foot to two feet of snow on the ground, along with many areas in upstream river basins in Minnesota and the Dakotas having similar or deeper snowpacks on the ground. Additionally, with the below...
Flood — Oct 1, 2018
A frontal boundary resided predominantly right along the Iowa-Missouri border and remained relatively stationary throughout the event. Beginning on September 30th, 850mb flow rode over the front and helped initiated elevated showers and weak storms that persisted (scattered in nature) form the late afternoon of the 30th through the late afternoon on the 1st. While no severe weather was recorded...
Flood — Jul 1, 2018
Very heavy rain fell across the Des Moines and Waterloo metro areas on the evening of June 30th. This led to flash flooding and river flooding that continued into 01 July 2018. Some of the rivers remained in flood through much of July, and the West Fork of the Des Moines River at Estherville remained in flood through nearly all of July. ||Previous write-up from 30 June 2018|A frontal boundary w...
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 Grundy 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 Grundy 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.