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

Calhoun County Disaster Risk

Calhoun County, Iowa

FEMA Risk Rating

Relatively Low

National Percentile

45th

of 3,144 counties

State Rank

#32

of 99 (1 = highest risk)

Flood Risk

21th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Very Low

Higher than 21% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Very Low

Higher than 8% of US counties

Tornado

Tornado and severe thunderstorm risk

Relatively Low

Higher than 74% 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 15% of US counties

Risk Overview

About Natural Disaster Risk in Calhoun County, Iowa

Calhoun edges into above-average territory

With a composite risk score of 44.56, Calhoun County rates as Relatively Low—still safe by national standards but noticeably above the typical U.S. county. This marks a meaningful step up from Iowa's safest communities.

Iowa's riskier half takes hold

Calhoun's 44.56 score exceeds Iowa's state average of 39.68 by 12%, placing it firmly in the higher-risk segment of Iowa counties. The county ranks in the upper third for natural disaster exposure across the state.

Risk spike moving westward

Calhoun (44.56) represents a dramatic jump from eastern neighbors Bremer (24.55), Buchanan (24.05), and Butler (27.10). It sits below the dangerous western duo of Carroll (57.60) and Cass (60.05), and matches Cedar County's relative position eastward.

Tornadoes dwarf all other threats

Tornado risk of 73.63 dominates Calhoun's hazard profile—among the highest in Iowa. Earthquake risk (14.60), hurricane risk (14.69), wildfire risk (8.49), and flood risk (20.61) are all substantially lower by comparison.

Tornado safety planning is critical

Calhoun residents face one of Iowa's highest tornado risks and must develop a detailed household shelter plan before storm season. Ensure your insurance includes comprehensive wind and hail coverage, and practice tornado drills with your family annually.

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

Preparedness Guide

What to Prepare for in Calhoun County

Top Hazards by Exposure

  1. #1
    TornadoPrepare
    74th percentile
  2. #2
    FloodPrepare
    21th percentile
  3. #3
    HurricanePrepare
    15th percentile

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

Risk Advisory: Calhoun County

Risk Verdict

Calhoun County sits below the national average for natural disaster exposure, ranking at the 45th percentile across all U.S. counties. A 45th percentile score positions Calhoun County among the nation's lower-risk counties, a genuinely favorable outcome — one that simple, low-cost preparedness habits can reinforce further.

Hazard Breakdown

Tornado risk is Calhoun County's dominant natural hazard, ranked at the 74th percentile nationally under FEMA's National Risk Index. Flood ranks second at the 21th percentile nationally. Additional tracked hazards include hurricane (15th percentile), earthquake (15th percentile), wildfire (8th percentile).

Preparedness Context

Ranked at the 74th percentile nationally for tornado risk, Calhoun County is in a zone where storm shelters have the highest per-dollar protective value of any mitigation investment. Calhoun County's county shelter map is typically available through the local emergency management office. Flood is the second hazard driver for Calhoun County at the 21th percentile nationally, meaning households should maintain awareness of both severe-weather and flood-specific warning systems. Calhoun 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

Calhoun County's composite risk score is within 4.9 points of the Iowa county average — a close alignment that reflects a broadly representative hazard environment for this part of the state.

Is your household prepared for Calhoun 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 Calhoun County, IA?
Calhoun County has a FEMA National Risk Index rating of Relatively Low, placing it in the 45th 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 Calhoun County?
Calhoun County is evaluated for five major natural hazard types: tornado (74th percentile), flooding (21th percentile), hurricane (15th percentile), earthquake (15th percentile), wildfire (8th percentile). The highest-risk hazard is tornado at the 74th 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 Calhoun County risk compare to the Iowa average?
Calhoun County's composite risk percentile is 45th, compared to the Iowa state average of 40th percentile. The state's overall risk rating is Very Low. This means Calhoun County faces higher natural disaster risk than the typical county in Iowa.
Is Calhoun County at risk for tornado?
Yes, Calhoun County's tornado risk is at the 74th percentile nationally. This is above the national median. For flooding specifically, Calhoun County is at the 21th 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 Calhoun County higher risk than average?
Calhoun County's composite risk score of 45th percentile is above the Iowa state average of 40th percentile. This elevated risk is driven by tornado exposure (74th percentile). 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.