Hamilton County, Illinois
Natural disaster risk, federal disaster history and flood insurance facts.
Hamilton County, Illinois has a very low overall risk from natural hazards in FEMA's National Risk Index. Its risk score is lower than 69% of US counties. It ranks 79th of 102 counties in Illinois. The costliest hazards here are earthquakes, inland flooding and tornadoes. FEMA estimates about $12 million a year in expected losses, or roughly $1,566 per resident. Since 1989 it has been included in 8 federal disaster or emergency declarations for natural events (6 major disasters). The most recent was in June 2011 (severe storms and flooding). No homes here carry federal flood insurance.
FEMA National Risk Index December 2025; OpenFEMA declarations to Nov 6, 2026; NFIP records. Updated November 6, 2026.
Top risks in Hamilton County
- Ask whether an older house is bolted to its foundation.
- Consider separate earthquake insurance where risk is high.
- Check the FEMA flood map for your address, and ask the seller or landlord about past flooding.
- Price a flood policy now. Most new federal policies take 30 days to start.
- Pick a shelter spot: a basement, or an inside room on the lowest floor with no windows.
- Turn on emergency alerts on your phone and keep a weather radio.
All 18 hazards
What the ratings mean ›| Hazard | Rating | Score | Expected loss a year | |
|---|---|---|---|---|
| Earthquake | 90.7 | $7M | ||
| Inland flooding | 12.5 | $2M | ||
| Tornado | 37.3 | $939K | ||
| Strong wind | 55.9 | $803K | ||
| Cold wave | 30.9 | $545K | ||
| Heat wave | 44.1 | $345K | ||
| Drought | 52.7 | $218K | ||
| Hail | 35.1 | $180K | ||
| Winter weather | 53.1 | $88K | ||
| Ice storm | 36.2 | $55K | ||
| Lightning | 12.3 | $52K | ||
| Hurricane | 27.8 | $15K | ||
| Landslide | 49.0 | $2K | ||
| Wildfire | 1.1 | $598 |
Scores are percentiles: a score of 90 means higher risk than about 90% of US counties for that hazard. Hazards FEMA does not rate here are left out. Social vulnerability is very low and community resilience is relatively high in FEMA's measures.
Federal disaster history
Recent disasters nationwide ›Declarations by decade
Federal declarations for natural events that included Hamilton County. 2020s bar runs to November 2026.
By type
Most recent
Illinois also had 2 statewide declarations that did not name single counties.
Storm history since 1957
Tornado risk by county ›The National Weather Service has logged 177 storm reports in Hamilton County since 1957, with 0 deaths and 9 injuries and about $11.7 million in reported damage. The strongest on record here was an F4 tornado on June 2, 1990.
Strongest tornadoes
| Date | Strength | Near | Hurt / killed |
|---|---|---|---|
| Jun 2, 1990 | F4 | – | 0 / 0 |
| Apr 19, 1996 | F3 | Piopolis | 0 / 0 |
| Dec 18, 1957 | F3 | – | 4 / 0 |
| Dec 18, 1957 | F3 | – | 3 / 0 |
| Jan 7, 1989 | F2 | – | 0 / 0 |
Most damaging storms
| Date | Type | Near | Damage |
|---|---|---|---|
| Apr 19, 1996 | Tornado | Piopolis | $3M |
| Jan 7, 1989 | Tornado | – | $3M |
| Jun 2, 1990 | Tornado | – | $3M |
| Apr 24, 2002 | Hail | Dahlgren | $750K |
| Mar 18, 2008 | Flood | Dahlgren | $340K |
| Dec 18, 1957 | Tornado | – | $250K |
Source: NOAA Storm Events Database, county-based reports through Oct 19, 2025. Tornado records start in 1950, hail and wind in 1955, and floods and other storm types in 1996, so older decades undercount. Damage is in dollars of the year it happened and is often an estimate. Winter storms, heat and hurricanes are logged by forecast zone, not county, so they are not counted here.
Flood insurance in Hamilton County
Check your address flood zone ›National Flood Insurance Program (NFIP) records only; private flood policies are not included. Home counts as of Aug 3, 2026. Since 2021 NFIP prices each home separately under Risk Rating 2.0, so your price depends on the building, not the county. Ask an agent for a quote.
Homes in Hamilton County
Older homes and mobile homes usually suffer more damage in storms, floods and earthquakes, and can cost more to insure. If you are buying, ask about roof age, foundation bolting and any retrofits. Source: US Census Bureau, American Community Survey 2020 to 2024 5-year estimates; 3,803 housing units.
Compare in Illinois
All 102 ›| Largest counties | Overall risk | Top hazard |
|---|---|---|
| Cook County | Inland flooding | |
| DuPage County | Inland flooding | |
| Lake County | Inland flooding | |
| Will County | Inland flooding | |
| Kane County | Inland flooding | |
| McHenry County | Inland flooding | |
| Winnebago County | Inland flooding | |
| Madison County | Inland flooding |
Neighboring counties
| County | Overall risk | Declarations |
|---|---|---|
| Franklin County | 8 | |
| Jefferson County | 3 | |
| Saline County | 7 | |
| Wayne County | 6 | |
| White County | 8 | |
| Gallatin County | 9 |
Common questions about Hamilton County
What is the biggest natural hazard in Hamilton County?
Earthquake has the highest expected yearly losses in Hamilton County, about $7.3 million a year in FEMA's estimate. Inland flooding is second at $1.9 million.
How many federal disasters has Hamilton County had?
Hamilton County has been included in 8 federal disaster or emergency declarations for natural events since 1989, including 6 major disasters. The most recent was Severe Storms and Flooding in June 2011.
Is Hamilton County a high-risk place to live?
Its overall rating is Very Low, 79th highest of 102 in Illinois. A county rating covers the whole area. Risk at one address can be much higher or lower, so check the FEMA flood map and ask about the home's history.
Do I need flood insurance in Hamilton County?
Standard home insurance does not cover flooding. Lenders require it in mapped high-risk zones, but many flood claims come from outside those zones.
How many tornadoes has Hamilton County had?
NOAA records list 12 tornadoes in Hamilton County since 1950. The strongest was an F4 tornado on June 2, 1990. The weather service has also logged 44 hail reports and 46 floods here.
Sources: FEMA National Risk Index (December 2025), OpenFEMA Disaster Declarations Summaries, and NFIP policy and claims data. Hazard Compass is independent and not affiliated with FEMA. These figures describe the whole county, not a single property, and are not insurance or safety advice. Report a problem.