St. Clair County, IL
FEMA National Risk Index scores, disaster declarations & hazard data
St. Clair County has experienced 19 federally declared disasters since 1968, most recently Severe Storms, Tornadoes, Straight-Line Winds, And Floodng in 2024. Its overall natural hazard risk is rated Relatively High — higher risk than most US counties.
St. Clair County's highest-rated hazards are heat wave, earthquake, and hail, with its top risk rated "Relatively High" by FEMA's National Risk Index. Recorded storm events have increased 30% over the past five years compared to the prior five-year period.
Past disasters & FEMA designations
A federal disaster declaration officially designates a county for FEMA disaster assistance. St. Clair County has been designated in 19 declarations since 1968, covering 6 disaster types including flood (8), severe storm (5), biological (2).
| Year | Type | Event name |
|---|---|---|
| 2024 | Flood | Severe Storms, Tornadoes, Straight-Line Winds, And Floodng |
| 2023 | Flood | Severe Storm And Flooding |
| 2020 | Biological | Covid-19 Pandemic |
| 2020 | Biological | Covid-19 |
| 2019 | Flood | Severe Storms And Flooding |
| 2008 | Severe Storm | Severe Storms And Flooding |
| 2007 | Severe Ice Storm | Severe Winter Storm |
| 2005 | Hurricane | Hurricane Katrina Evacuation |
| 2002 | Tornado | Severe Storms, Tornadoes And Flooding |
| 1996 | Severe Storm | Severe Storms And Flooding |
Showing the 10 most recent of 19 total declarations since 1968.
Source: FEMA OpenFEMA Disaster Declarations Summaries. A single disaster can produce more than one record per county. Data current through September 2026.
Risk by hazard type
| Hazard | Risk rating | Risk score | Recorded events | Deaths | Prop. damage |
|---|---|---|---|---|---|
| Wildfire | Very Low | 15.1 | 0 | 0 | — |
| Inland Flooding | Relatively High | 94.5 | 17 | 0 | $18.2M |
| Coastal Flooding | Not Applicable | — | 0 | 0 | — |
| Earthquake | Relatively Moderate | 98 | — | — | — |
| Heat Wave | Relatively High | 98.1 | 14 | 0 | — |
| Tornado | Relatively High | 95.5 | 16 | 0 | $461K |
| Hurricane | Very Low | 34.9 | 0 | 0 | — |
| Hail | Relatively High | 97.6 | 55 | 0 | — |
| Strong Wind | Relatively Moderate | 54 | 0 | 0 | — |
| Winter Weather | Relatively High | 87.2 | 0 | 0 | — |
| Ice Storm | Relatively High | 91 | — | — | — |
| Cold Wave | Relatively High | 96.4 | — | — | — |
| Lightning | Relatively High | 93.7 | 1 | 1 | — |
| Drought | Relatively Low | 61.4 | 0 | 0 | — |
| Landslide | Relatively Low | 84.3 | 0 | 0 | — |
| Avalanche | Not Applicable | — | — | — | — |
| Tsunami | Not Applicable | — | — | — | — |
| Volcanic Activity | Not Applicable | — | — | — | — |
Scores are 0–100 percentiles relative to all US counties — higher means more exposed, not that a disaster is likely this year. Event counts: NOAA Storm Events 2016–2026; earthquake counts from USGS ComCat (M3.0+, 1996–2026). See the methodology page for details.
Community vulnerability
St. Clair County ranks in the 53rd percentile (Moderate) for community vulnerability — a measure of how hard disaster impacts tend to hit residents. Higher vulnerability means more displacement, worse health outcomes, and slower recovery after a disaster.
| SVI theme | Percentile | Vulnerability level |
|---|---|---|
| Overall | 53rd | Moderate |
| Socioeconomic status | 44th | Low |
| Household characteristics | 59th | Moderate |
| Racial & ethnic minority status | 78th | High |
| Housing type & transportation | 45th | Low |
Source: CDC/ATSDR Social Vulnerability Index 2022. Percentiles compare counties nationally — higher means more vulnerable relative to other counties. See CDC SVI for full methodology.
Future risk outlook
| Wildfire metric | National percentile | Level |
|---|---|---|
| Burn probability | 6th | Very Low |
| Risk to homes | 6th | Very Low |
| Buildings in direct exposure zone | 16.1% | — |
NOAA tracked 101 weather events in this county over 2016–2025: 44 in 2016–20 vs 57 in 2021–25 (+30% — frequency increasing).
Wildfire: USDA Forest Service Wildfire Risk to Communities (RDS-2020-0016-2) — modeled values, not annual forecasts. See wildfirerisk.org. Inland flood and heat projections pending data availability; coastal sea-level projections are available for select coastal counties below — see the data page.
Nearby counties
Frequently asked questions
What natural hazards pose the greatest risk in St. Clair County?
According to the FEMA National Risk Index, the highest-risk hazards in St. Clair County, Illinois are heat wave, earthquake, and hail. The county's overall natural hazard risk is rated Relatively High — higher risk than most US counties.
Has St. Clair County received federal disaster declarations?
Yes. St. Clair County has received 19 federal disaster declarations since 1968, including declarations in 2024. The most common disaster type on record is flood (8 declarations).
Has St. Clair County had any FEMA disaster declarations in 2024, 2025, or 2026?
Yes. Recent federal disaster declarations for St. Clair County include Severe Storms, Tornadoes, Straight-Line Winds, And Floodng (2024). See the declarations table above for the full history since 1968.
How does St. Clair County's natural hazard risk compare to nearby counties?
Among neighboring counties, St. Louis, MO has the highest overall natural hazard risk (Relatively High) and Monroe County, IL has the lowest (Very Low). St. Clair County is rated Relatively High overall.
How is St. Clair County's composite disaster risk index calculated?
St. Clair County's composite disaster risk index — officially FEMA's National Risk Index (NRI) — scores every US county on a 0–100 percentile scale across 18 natural hazard types, factoring in expected annual loss, social vulnerability, and community resilience. St. Clair County's composite score of 95 means its overall natural hazard risk is higher than 95% of US counties.