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

Clarke County Disaster Risk

Clarke County, Iowa

FEMA Risk Rating

Very Low

National Percentile

18th

of 3,144 counties

State Rank

#88

of 99 (1 = highest risk)

Flood Risk

10th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Very Low

Higher than 10% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Very Low

Higher than 42% of US counties

Tornado

Tornado and severe thunderstorm risk

Relatively Low

Higher than 45% of US counties

Earthquake

Seismic activity and ground shaking risk

Very Low

Higher than 15% of US counties

Hurricane

Tropical cyclone and hurricane risk

Very Low

Higher than 8% of US counties

Risk Overview

About Natural Disaster Risk in Clarke County, Iowa

Clarke County is Iowa's safest

Clarke's composite risk score of 18.38 ranks among the lowest in the nation, far exceeding the safety of Iowa's average county (39.68). Residents here face minimal natural disaster exposure compared to almost any American region.

Lowest risk of all Iowa counties

Clarke ranks last (safest) among Iowa's 99 counties with its 18.38 composite score. This exceptional safety reflects favorable geography and climate characteristics that protect the county from most major hazards.

Significantly safer than neighbors

Clarke's 18.38 score stands markedly below neighboring Clayton (42.21) and Clinton (64.82), making it an island of relative safety in a region with more hazard exposure. This distinction reflects Clarke's unique positioning in south-central Iowa.

Wildfire emerges as primary concern

Clarke's wildfire risk of 42.02 represents its highest single hazard exposure, though still below state average. Tornado (44.59), flood (9.64), and earthquake (14.85) risks all remain exceptionally low.

Standard homeowners insurance adequate

Clarke's minimal risk profile means most homeowners can rely on standard policies for adequate coverage. Residents with wildland-adjacent properties should ensure their coverage includes brush clearance and defensible space improvements.

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

Preparedness Guide

What to Prepare for in Clarke County

Top Hazards by Exposure

  1. #1
    TornadoPrepare
    45th percentile
  2. #2
    WildfirePrepare
    42th percentile
  3. #3
    EarthquakePrepare
    15th percentile

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

Local Resources

Risk Advisory: Clarke County

Risk Verdict

Natural disaster exposure in Clarke County is lower than roughly three-quarters of U.S. counties, with a composite score at the 18th percentile. Clarke County's 18th percentile ranking is favorable, though every county carries at least one natural hazard worth knowing — reviewing the specific risks listed above helps households focus their preparedness where it matters most.

Hazard Breakdown

Tornado risk is Clarke County's dominant natural hazard, ranked at the 45th percentile nationally under FEMA's National Risk Index. Wildfire ranks second at the 42th percentile nationally. Additional tracked hazards include earthquake (15th percentile), flood (10th percentile), hurricane (8th percentile).

Preparedness Context

Ranked at the 45th percentile nationally for tornado risk, Clarke County is in a zone where storm shelters have the highest per-dollar protective value of any mitigation investment. Clarke County's county shelter map is typically available through the local emergency management office. Alongside tornado exposure, wildfire at the 42th percentile nationally means Clarke County households face multi-hazard severe-weather seasons that benefit from a single integrated emergency plan covering both threats. Clarke 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

Clarke County is 21.3 composite risk points below the Iowa state mean, meaning most other Iowa counties face higher natural hazard exposure.

Is your household prepared for Clarke 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 Clarke County, IA?
Clarke County has a FEMA National Risk Index rating of Very Low, placing it in the 18th 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 Clarke County?
Clarke County is evaluated for five major natural hazard types: tornado (45th percentile), wildfire (42th percentile), earthquake (15th percentile), flooding (10th percentile), hurricane (8th percentile). The highest-risk hazard is tornado at the 45th 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 Clarke County risk compare to the Iowa average?
Clarke County's composite risk percentile is 18th, compared to the Iowa state average of 40th percentile. The state's overall risk rating is Very Low. This means Clarke County faces lower natural disaster risk than the typical county in Iowa.
Is Clarke County at risk for tornado?
Yes, Clarke County's tornado risk is at the 45th percentile nationally. This is below the national median, indicating relatively lower exposure. For flooding specifically, Clarke County is at the 10th 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.
Is Clarke County a safe place to live?
Clarke County's composite risk score of 18th percentile is below the Iowa state average of 40th percentile, indicating relatively lower exposure to natural hazards. However, no county is completely risk-free. The primary hazard type is tornado at the 45th percentile. Residents should still maintain emergency preparedness plans and appropriate insurance coverage.

Counties with Similar Risk

Ida County

Iowa

-0.0

Very Low

18th percentile

Mills County

Iowa

+0.1

Very Low

18th percentile

Lyon County

Iowa

+0.8

Very Low

19th percentile

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.

Explore more data for Clarke County

Property TaxCost of LivingCrime RateIncomeHealthSchoolsWater QualityWeatherCounty Score