Natural disaster risk in Illinois

How disaster-prone is Illinois?

Illinois (IL) sits at a low level of federally recognized natural-disaster risk, with 5 FEMA disaster declarations on record, including 4 Major Disaster declarations (DR) that triggered full federal individual and public assistance. The dominant declaration type is Flood, followed by Severe Storm (1), Tornado (1). Declaration counts at the state level reflect the cumulative federal footprint: large multi-county events count once per state, but repeat hazard patterns across decades are visible in the breakdown below.

NOAA's Storm Events Database adds the near-term severe-weather lens. Between 2015 and 2025, Illinois recorded 24,790 individual storm events, causing 176 fatalities and 528 injuries, with combined property and crop damage estimated at $2.1B. The most frequent event types in the state are Thunderstorm Wind (8,196 events), Hail (3,526 events), Winter Weather (1,524 events). Across the state's 37 analyzed counties, FEMA's own National Risk Index flags 3 as high-risk, with an average county Risk Index score (FEMA's own formula, distinct from our Risk Score tool below) of 53.2/100.

NFIP claims data is limited or absent for this state in the current extract, which usually indicates low flood-policy penetration rather than zero flood risk. The highest-Expected-Annual-Loss hazard across the state is Cold Wave, estimated at $0.9B annually. Drill into individual counties for localized risk, read FEMA's hazard-specific briefings, and review insurance and flood-zone designations, state-level averages can mask sharp county-to-county differences in exposure and resilience.