Jefferson County, Illinois

Jefferson County, Illinois has a relatively low overall risk from natural hazards in FEMA's National Risk Index. Its risk score is higher than 77% of US counties. It ranks 27th of 102 counties in Illinois. The costliest hazards here are earthquakes, inland flooding and tornadoes. FEMA estimates about $34 million a year in expected losses, or roughly $921 per resident. Since 2002 it has been included in 3 federal disaster or emergency declarations for natural events (2 major disasters). The most recent was in June 2011 (severe storms and flooding). Only 20 homes here carry federal flood insurance. Since 1978, federal flood insurance has paid about $262,000 on 13 claims here.

FEMA National Risk Index December 2025; OpenFEMA declarations to Nov 6, 2026; NFIP records. Updated November 6, 2026.

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 relatively moderate and community resilience is relatively high in FEMA's measures.

The National Weather Service has logged 332 storm reports in Jefferson County since 1955, with 7 deaths and 64 injuries and about $29.2 million in reported damage. The strongest on record here was an F4 tornado on December 18, 1957.

Source: NOAA Storm Events Database, county-based reports through Apr 27, 2026. 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.

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.

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; 16,629 housing units.

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.