riskbycounty
FEMA NRI 1.19.0Updated Nov 2023 · Coverage 2014–2023Methodology

Stephenson County Disaster Risk

Stephenson County, Illinois

FEMA Risk Rating

Relatively Low

National Percentile

74th

of 3,144 counties

State Rank

#30

of 102 (1 = highest risk)

Flood Risk

78th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Relatively Low

Higher than 78% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Very Low

Higher than 27% of US counties

Tornado

Tornado and severe thunderstorm risk

Moderate

Higher than 82% of US counties

Earthquake

Seismic activity and ground shaking risk

Relatively Low

Higher than 58% of US counties

Hurricane

Tropical cyclone and hurricane risk

Very Low

Higher than 15% of US counties

Risk Overview

About Natural Disaster Risk in Stephenson County, Illinois

Stephenson ranks above average nationally

With a composite risk score of 73.92, Stephenson County faces above-average natural disaster risk compared to most U.S. counties. This "Relatively Low" rating reflects meaningful exposure to tornadoes and flooding, the county's two dominant hazards.

Above Illinois average, middle of the pack

Stephenson's 73.92 score significantly exceeds Illinois's state average of 54.46, placing it in the higher-risk tier among the state's 102 counties. The county ranks notably above many southern and central Illinois peers.

Riskier than nearby Warren County

Stephenson faces notably higher disaster risk than its western neighbor Warren County (15.49), driven by substantially higher tornado and flood exposure. However, Stephenson's risk profile is comparable to neighboring Tazewell County (84.19) to the south.

Tornadoes and floods dominate exposure

Tornado risk (82.25) and flood risk (77.93) are your county's primary natural hazards, each well above national and state averages. While earthquake risk registers at 57.67, the immediate threat comes from severe weather events that develop rapidly across Illinois's flat terrain.

Prioritize flood and tornado coverage

Standard homeowners insurance doesn't cover flood damage—you need a separate flood policy, especially critical given your county's 77.93 flood risk score. Consider a safe room or shelter reinforcement for tornadoes, and ensure your policy includes wind and hail coverage for severe thunderstorms.

Source: FEMA National Risk Index · Narrative reviewed by Evan Brooks, Data Editor

Preparedness Guide

What to Prepare for in Stephenson County

Top Hazards by Exposure

  1. #1
    TornadoPrepare
    82th percentile
  2. #2
    FloodPrepare
    78th percentile
  3. #3
    EarthquakePrepare
    58th percentile

Source: FEMA National Risk Index v1.19.0 · Percentiles are national (3,144 counties)

Risk Advisory: Stephenson County

Risk Verdict

Stephenson County sits below the national average for natural disaster exposure, ranking at the 74th percentile across all U.S. counties. Understanding the specific hazards behind Stephenson County's ranking helps residents prioritize where to direct emergency planning efforts.

Hazard Breakdown

Tornado risk is Stephenson County's dominant natural hazard, ranked at the 82th percentile nationally under FEMA's National Risk Index. Flood ranks second at the 78th percentile nationally. Additional tracked hazards include earthquake (58th percentile), wildfire (27th percentile), hurricane (15th percentile).

Preparedness Context

Ranked at the 82th percentile nationally for tornado risk, Stephenson County is in a zone where storm shelters have the highest per-dollar protective value of any mitigation investment. Stephenson County's county shelter map is typically available through the local emergency management office. Flood is the second hazard driver for Stephenson County at the 78th percentile nationally, meaning households should maintain awareness of both severe-weather and flood-specific warning systems. Stephenson County residents can check the county's emergency management website for community shelter locations nearest their address — a step worth completing now, not during a warning.

Regional Context

A composite score 19.5 points above the Illinois state average puts Stephenson County in a higher-risk category than most counties in the state.

Is your household prepared for Stephenson County's hazards?

Review FEMA's county-specific preparedness checklists and emergency planning guides.

FEMA Ready Guide →

Frequently Asked Questions

What is the natural disaster risk in Stephenson County, IL?
Stephenson County has a FEMA National Risk Index rating of Relatively Low, placing it in the 74th percentile nationally out of 3,144 counties. This composite score reflects the county's overall exposure to natural hazards including floods, wildfires, tornadoes, earthquakes, and hurricanes, weighted by expected annual loss and social vulnerability.
What types of natural hazards affect Stephenson County?
Stephenson County is evaluated for five major natural hazard types: tornado (82th percentile), flooding (78th percentile), earthquake (58th percentile), wildfire (27th percentile), hurricane (15th percentile). The highest-risk hazard is tornado at the 82th percentile nationally. These scores are derived from FEMA's National Risk Index, which analyzes expected annual loss, social vulnerability, and community resilience for each hazard type.
How does Stephenson County risk compare to the Illinois average?
Stephenson County's composite risk percentile is 74th, compared to the Illinois state average of 55th percentile. The state's overall risk rating is Relatively Low. This means Stephenson County faces higher natural disaster risk than the typical county in Illinois.
Is Stephenson County at risk for tornado?
Yes, Stephenson County's tornado risk is at the 82th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Stephenson County is at the 78th percentile.
How is natural disaster risk measured?
FEMA's National Risk Index (NRI) calculates risk scores for 18 natural hazard types across all U.S. counties and census tracts. The composite score combines Expected Annual Loss (estimated dollar losses from each hazard), Social Vulnerability (demographic factors affecting disaster impact), and Community Resilience (ability to recover). Percentile scores rank each county against all 3,144 U.S. counties, and risk ratings range from Very Low to Very High.
Why is Stephenson County higher risk than average?
Stephenson County's composite risk score of 74th percentile is above the Illinois state average of 55th percentile. This elevated risk is driven by tornado exposure (82th percentile), along with flooding and earthquake risk. Geographic location, terrain, climate patterns, and proximity to flood zones or fault lines all influence a county's risk profile.
By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor

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.