Enter any address in Calhoun County, Illinois to see its FEMA flood zone
Flash flooding from heavy rainfall events dominates the flood character of Calhoun County. Recent examples include flash flooding on July 27, 2025, caused by thunderstorms that trained over the county, leading to flooded roads and washed-out culverts. On June 19, 2021, widespread storms triggered by an outflow boundary resulted in flash flooding alongside reports of hail and damaging winds.
National Flood Insurance Program (NFIP) data indicates that properties in Zone A have experienced the highest number of claims, with an average payout of $10,836 and an average water depth of 4.4 feet. Properties in Zone X and Zone X_Shaded have also seen significant payouts, averaging $13,583 and $14,177 respectively, with Zone X_Shaded experiencing an average water depth of 4.7 feet. Homeowners in Zone A, Zone X_Shaded, and those located near waterways or in areas with lower elevations should pay the most attention to flood risk.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
3 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Calhoun County, Illinois has recorded 28 flood-related events since 1996 according to NOAA's Storm Events Database, including 13 flash floods and 15 river or area floods. The county has received 25 federal disaster declarations, 11 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1969–2023)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| Severe Storms And Flooding | Severe Storm | Jun 29, 2023 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Severe Storms And Flooding | Flood | Feb 24, 2019 |
| 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 | Jun 1, 2008 |
| Severe Winter Storm | Severe Ice Storm | Nov 30, 2006 |
| Hurricane Katrina Evacuation | Hurricane | Aug 29, 2005 |
| Severe Storms, Tornadoes And Flooding | Tornado | Apr 21, 2002 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flash Flood | Jul 27, 2025 | 50.00K |
| Flash Flood | Jun 19, 2021 | 0.00K |
| Flash Flood | Jun 25, 2015 | 0.00K |
| Flash Flood | Jun 21, 2015 | 0.00K |
| Flash Flood | Oct 2, 2014 | 0.00K |
| Flood | Apr 16, 2013 | 5.00K |
| Flood | Apr 12, 2013 | 1.00K |
| Flood | May 1, 2013 | 2.00K |
| Flood | Jun 1, 2013 | 1.00K |
| Flood | Jun 14, 2010 | 0.00K |
Flash Flood — Jul 27, 2025
During the night of July 26th-July 27th, moisture convergence along a low-level jet spurred convection in eastern Missouri. This convection developed in an environment primed for efficient and heavy rainfall. Thunderstorms trained over Calhoun County, causing roads to flood and culverts to wash out.
Flash Flood — Jun 19, 2021
An outflow boundary from earlier convection moved southward through region, triggering widespread storms. Some of the storms became severe with numerous reports of large hail, damaging winds and flash flooding.
Flash Flood — Jun 25, 2015
A frontal boundary was slowly sinking south across forecast area. Several rounds of storms developed and moved east along the front dumping up to 8 inches of rain in a 24 hour period from 7 am June 25th to 7 am June 26th. This caused considerable flash flooding, especially in Lincoln County Missouri and Calhoun County Illinois. There were also numerous reports of damaging winds and large hail.
Flash Flood — Jun 21, 2015
A cold front moved into the region and stalled out, triggering showers and thunderstorms. A number of thunderstorms developed across northern Missouri and west central Illinois. Heavy rain from the storms caused flash flooding across the region.
Flash Flood — Oct 2, 2014
Additional severe storms developed during the late morning through evening hours of Oct. 2nd. There were several reports of flash flooding, damaging winds and hail.
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 Calhoun 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 Calhoun 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.