St. Clair County Disaster Risk
St. Clair County, Michigan
FEMA Risk Rating
Relatively Moderate
National Percentile
82th
of 3,144 counties
State Rank
#11
of 83 (1 = highest risk)
Flood Risk
86th
percentile
Hazard Risk Breakdown
Flood
River, coastal, and surface flooding risk
Moderate
Higher than 86% of US counties
Wildfire
Wildland and wildland-urban interface fire risk
Very Low
Higher than 34% of US counties
Tornado
Tornado and severe thunderstorm risk
Moderate
Higher than 87% of US counties
Earthquake
Seismic activity and ground shaking risk
Relatively Low
Higher than 51% of US counties
Hurricane
Tropical cyclone and hurricane risk
Very Low
Higher than 36% of US counties
Risk Overview
About Natural Disaster Risk in St. Clair County, Michigan
St. Clair faces significant disaster exposure
St. Clair County scores 82.00 on the composite risk scale, placing it well above Michigan's state average of 49.56 and in the "Relatively Moderate" risk category. This elevated rating reflects meaningful exposure across multiple hazard types, particularly tornadoes and flooding. The county ranks among Michigan's more hazardous regions and demands serious disaster preparedness from residents.
Among Michigan's highest-risk counties
St. Clair County ranks as one of Michigan's riskier counties statewide, with a composite score about 65% above the state average. Elevated tornado (87.21), flood (85.94), and moderate wildfire (33.52) risks drive this ranking. This positioning places St. Clair residents in territory requiring substantive natural disaster awareness and preparation.
Riskiest county in its regional cluster
St. Clair's score of 82.00 significantly exceeds nearby Sanilac County (70.32) and Tuscola County (73.06), making it the region's highest-risk area. Only Saginaw County (88.55) surpasses St. Clair's exposure in this part of Michigan, creating a small cluster of notably hazardous counties. Regional geographic and weather patterns concentrate disaster risk in these neighboring communities.
Tornadoes and floods are principal threats
St. Clair County faces exceptionally high tornado risk (87.21) and severe flood risk (85.94), both among Michigan's highest—these two hazards constitute the core disaster danger. Earthquake exposure is moderate at 50.83, while wildfire and hurricane risks remain in the low-to-moderate range. Residents must prioritize tornado shelter access and flood-resistant building as foundational safety strategies.
Comprehensive flood and wind protection needed
St. Clair's 85.94 flood risk score demands that residents in flood-prone areas secure separate flood insurance, as standard homeowners policies exclude water damage. Ensure your homeowners policy provides robust wind and hail coverage adequate for the county's 87.21 tornado risk. Professional assessment of basement waterproofing and roof condition can identify cost-effective vulnerability reductions.
Source: FEMA National Risk Index · Narrative reviewed by Evan Brooks, Data Editor
Preparedness Guide
What to Prepare for in St. Clair County
Top Hazards by Exposure
Source: FEMA National Risk Index v1.19.0 · Percentiles are national (3,144 counties)
Risk Advisory: St. Clair County
Risk Verdict
St. Clair County's overall risk score at the 82th percentile nationally signals meaningful exposure to multiple natural hazard types. Comprehensive household preparedness — including reviewing insurance, maintaining emergency supplies, and knowing evacuation routes — is strongly recommended.
Hazard Breakdown
Tornado risk is St. Clair County's dominant natural hazard, ranked at the 87th percentile nationally under FEMA's National Risk Index. Flood ranks second at the 86th percentile nationally. Additional tracked hazards include earthquake (51th percentile), hurricane (36th percentile), wildfire (34th percentile).
Preparedness Context
St. Clair County ranks at the 87th percentile nationally for tornado exposure. Unlike many slow-onset hazards, tornadoes in St. Clair County can reach full intensity in minutes; a pre-practiced household shelter plan matters far more than stockpiled supplies. Flood is the second hazard driver for St. Clair County at the 86th percentile nationally, meaning households should maintain awareness of both severe-weather and flood-specific warning systems. St. Clair County county emergency management typically publishes annual severe-weather preparedness guides tailored to local tornado patterns; households benefit from reviewing these before storm season begins each spring.
Regional Context
Compared to other Michigan counties, St. Clair County runs 32.4 composite risk points higher than the state mean — reflecting above-average hazard concentration in this area.
Is your household prepared for St. Clair County's hazards?
Review FEMA's county-specific preparedness checklists and emergency planning guides.
Frequently Asked Questions
What is the natural disaster risk in St. Clair County, MI?
What types of natural hazards affect St. Clair County?
How does St. Clair County risk compare to the Michigan average?
Is St. Clair County at risk for tornado?
How is natural disaster risk measured?
Why is St. Clair County higher risk than average?
Data Source
Risk data sourced from the FEMA National Risk Index (NRI). Risk scores are relative rankings (0–100) across all US counties — not absolute risk measures. Higher scores indicate higher relative risk compared to other counties.
Disclaimer: This data is informational only. It is not financial, insurance, or legal advice. Always consult a qualified professional before making insurance or real estate decisions.