Enter any address in Winnebago County, Illinois to see its FEMA flood zone
Flash flooding from summer thunderstorms is the dominant flood character in Winnebago County. Between 1993 and 2023, NOAA Storm Events data recorded 53 flood events and 35 flash flood events, resulting in two fatalities. For example, localized flash flooding occurred around Rockford on July 10, 2025, following scattered thunderstorms. Additionally, torrential rainfall from thunderstorms led to widespread flash flooding across northern Illinois on August 18, 2025.
National Flood Insurance Program (NFIP) claims data indicates that properties in Zone A have experienced the most claims, with an average payout of $19,408 and an average water depth of 6.5 feet. Properties in Zone X and Zone X_Unshaded also show significant claim activity, with average payouts exceeding $12,000 and average water depths ranging from 1.2 to 3.3 feet. Homeowners in these zones, as well as those in Zone Unknown, should pay close attention to flood risk.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
22 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Winnebago County, Illinois has recorded 88 flood-related events since 1996 according to NOAA's Storm Events Database, including 35 flash floods and 53 river or area floods. The county has received 19 federal disaster declarations, 5 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1967–2024)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| Severe Storms, Tornadoes, Straight-line Winds, And Floodng | Flood | Jul 13, 2024 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Severe Storms, Straight-line Winds, And Flooding | Flood | Apr 16, 2013 |
| Severe Winter Storm And Snowstorm | Snowstorm | Jan 31, 2011 |
| Severe Storms And Flooding | Severe Storm | Jul 19, 2010 |
| Severe Storms And Flooding | Severe Storm | Jun 1, 2008 |
| Record Snow And Near Record Snow | Snowstorm | Feb 5, 2008 |
| Severe Storms And Flooding | Severe Storm | Aug 7, 2007 |
| Snow | Snowstorm | Nov 30, 2006 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flood | Jul 25, 2025 | 0.00K |
| Flood | Jun 18, 2025 | 0.00K |
| Flash Flood | Aug 18, 2025 | 0.00K |
| Flash Flood | Jul 10, 2025 | 30.00K |
| Flash Flood | Jun 22, 2024 | 0.00K |
| Flood | Jul 15, 2024 | 0.00K |
| Flood | Jul 14, 2024 | 0.00K |
| Flash Flood | Jul 14, 2024 | 0.00K (1 deaths) |
| Flash Flood | Jul 14, 2024 | 500.00K |
| Flash Flood | Jul 13, 2024 | 2.00M |
Flood — Jul 25, 2025
Isolated thunderstorms produced funnel clouds across central Illinois during the late morning of July 25th. A narrow line of thunderstorms developed over southeast DuPage and central Cook Counties during the late morning of July 25th and continued into the early afternoon producing torrential rainfall and widespread flash flooding. Scattered thunderstorms moved across portions of northern Ill...
Flood — Jun 18, 2025
A large system of low pressure produced widespread thunderstorms which impacted northern Illinois on the 18th. The storms produced damaging winds and torrential rainfall leading to instances of minor flooding during the early afternoon with additional heavy rain continuing into the evening.
Flash Flood — Aug 18, 2025
During the afternoon and evening of the 18th, a few rounds of thunderstorms brought torrential rainfall to much of northern Illinois resulting in flash flooding. One particularly strong storm also produced damaging winds in DeKalb County. Initial reports estimate $8.8 million in flood damages around northern and northeast Illinois, and around $2.5 million in the city of Chicago alone.
Flash Flood — Jul 10, 2025
Scattered thunderstorms moved across portions of northern Illinois during the afternoon of July 10th producing large hail, wind damage and heavy rain. Localized flash flooding occurred around Rockford. Additional thunderstorms moved across central portions of Illinois during the late evening of July 10th into the early morning of July 11th producing isolated wind damage.
Flash Flood — Jun 22, 2024
A line of severe thunderstorms dropped south across northern Illinois during the evening and night of the 22nd. The line produced four EF-0 tornadoes in addition to widespread wind damage across the Chicago metro. Many also saw torrential rainfall and localized flash flooding, particularly in extreme northeast Illinois north of the I-90 corridor where a widespread 3-6 of rain fell.
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 Winnebago County, Illinois:
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 Winnebago County, Illinois 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.