Enter any address in Marion County, Illinois to see its FEMA flood zone
Flash flooding from thunderstorms is the dominant flood character in Marion County. Over the last 30 years, the NOAA Storm Events Database recorded 31 flash flood events, resulting in 5 fatalities. For example, widespread heavy rain caused flash flooding across the county in August 2023, following earlier flash flooding in April 2025.
National Flood Insurance Program (NFIP) data indicates that properties in Zone A have experienced the most claims, with an average payout of $21,796 and an average water depth of 4.3 feet. While Zone X_Unshaded properties have seen fewer claims with minimal payouts and lower water depths, the potential for flooding exists across various zones. Residents in areas designated as Zone A, or those located near waterways, should pay particular attention to flood risks.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
6 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Marion County, Illinois has recorded 34 flood-related events since 1996 according to NOAA's Storm Events Database, including 31 flash floods and 3 river or area floods. The county has received 8 federal disaster declarations. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1990–2020)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Severe Storms And Flooding | Severe Storm | Apr 19, 2011 |
| Severe Winter Storm And Snowstorm | Snowstorm | Jan 31, 2011 |
| Hurricane Katrina Evacuation | Hurricane | Aug 29, 2005 |
| Severe Storms, Tornadoes And Flooding | Tornado | Apr 21, 2002 |
| Severe Storms And Tornadoes | Severe Storm | Apr 18, 1996 |
| Severe Storms, Tornadoes & Flooding | Severe Storm | May 15, 1990 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flood | Apr 29, 2025 | 0.00K |
| Flash Flood | Apr 4, 2025 | 100.00K |
| Flash Flood | Aug 3, 2023 | 0.00K |
| Flash Flood | Jul 17, 2022 | 0.00K |
| Flash Flood | Aug 21, 2021 | 0.00K |
| Flash Flood | Aug 21, 2019 | 0.00K |
| Flash Flood | Aug 13, 2019 | 0.00K |
| Flash Flood | Aug 12, 2019 | 0.00K |
| Flash Flood | Jun 5, 2019 | 0.00K |
| Flash Flood | Jun 11, 2018 | 0.00K |
Flood — Apr 29, 2025
During the afternoon of April 29th, a QLCS from Oklahoma and southern Kansas entered southwest Illinois. Although the QLCS had been decaying up to this point, it was still capable of producing severe weather. Wind damage, flooding, and hail were all reported as the complex passed from Randolph County through Marion County.
Flash Flood — Apr 4, 2025
A stationary front over southern Missouri along with ample mid-level forcing, moisture, and efficient rain processes resulted in flash flooding across portions of southwest and south central Illinois.
Flash Flood — Aug 3, 2023
Thunderstorms developed over central Missouri during the early evening hours. They moved east/southeast through the overnight hours. Numerous large hail and damaging wind reports were received. During the late evening through overnight hours, widespread heavy rain fell causing flash flooding. There was fairly widespread 1-3 rainfall totals, with isolated 6-8+ in central Missouri and south-centr...
Flash Flood — Jul 17, 2022
Several rounds of storms moved through Marion County during the early morning hours of July 17th causing isolated areas of flash flooding.
Flash Flood — Aug 21, 2021
A subtle upper-level shortwave associated with a cold front, draped across the county warning area, was advancing southeast, aiding widely scattered convection to develop ahead of the front in western Illinois. While instability was sufficient to support modest storms, a considerable lack of deep-layer shear and weak low-level lapse rates kept these cells far from severe strength. However, a fe...
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 Marion 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 Marion 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.