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

Carroll County Disaster Risk

Carroll County, Iowa

FEMA Risk Rating

Relatively Low

National Percentile

58th

of 3,144 counties

State Rank

#21

of 99 (1 = highest risk)

Flood Risk

38th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Very Low

Higher than 38% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Very Low

Higher than 29% of US counties

Tornado

Tornado and severe thunderstorm risk

Moderate

Higher than 85% of US counties

Earthquake

Seismic activity and ground shaking risk

Very Low

Higher than 20% of US counties

Hurricane

Tropical cyclone and hurricane risk

Very Low

Higher than 19% of US counties

Risk Overview

About Natural Disaster Risk in Carroll County, Iowa

Carroll County's risk rises noticeably

Carroll's composite risk score of 57.60 places it in the Relatively Low category—higher than 45% of U.S. counties. While still manageable, this represents a meaningful natural disaster exposure elevation for Iowa.

Among Iowa's higher-risk counties

At 57.60, Carroll exceeds Iowa's state average of 39.68 by 45%, ranking it well into the upper half of Iowa's counties. Only Cass County (60.05) and a handful of others present comparably elevated composite risk.

Highest risk in the immediate region

Carroll (57.60) far exceeds the safer eastern cluster of Bremer, Buchanan, Butler, and Cedar counties. It ranks second only to Cass (60.05) in its immediate vicinity, representing a dramatic risk escalation moving westward.

Tornado risk stands exceptional

Tornado risk of 85.46 is among Iowa's highest, presenting Carroll's dominant hazard concern. Flood risk (37.53), earthquake risk (19.75), and wildfire risk (28.53) all trail significantly, though wildfire exposure is elevated relative to the state average.

Comprehensive storm preparedness required

Carroll residents face one of Iowa's most severe tornado risks and need a robust household shelter plan with regular drills. Beyond wind and hail insurance, families should maintain a 72-hour emergency kit, monitor local weather closely during spring, and know multiple evacuation routes.

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

Preparedness Guide

What to Prepare for in Carroll County

Top Hazards by Exposure

  1. #1
    TornadoPrepare
    85th percentile
  2. #2
    FloodPrepare
    38th percentile
  3. #3
    WildfirePrepare
    29th percentile

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

Risk Advisory: Carroll County

Risk Verdict

With a national percentile rank of 58th, Carroll County faces below-average hazard exposure relative to U.S. counties as a whole. Above-average risk does not mean imminent danger; it signals that informed, hazard-specific preparedness has high value here.

Hazard Breakdown

Tornado risk is Carroll County's dominant natural hazard, ranked at the 85th percentile nationally under FEMA's National Risk Index. Flood ranks second at the 38th percentile nationally. Additional tracked hazards include wildfire (29th percentile), earthquake (20th percentile), hurricane (19th percentile).

Preparedness Context

At the 85th percentile nationally for tornado risk, Carroll County households benefit most from a reliable alert system — a NOAA weather radio that activates during overnight hours when residents may not be checking smartphone alerts. Alongside tornado exposure, flood at the 38th percentile nationally means Carroll County households face multi-hazard severe-weather seasons that benefit from a single integrated emergency plan covering both threats. For Carroll County households, a pre-decided family shelter plan — who goes where, how children are retrieved from school during a warning, and a neighborhood meet-up point if phones fail — provides real protection that no supply kit alone can replicate.

Regional Context

At 17.9 points above the Iowa state average, Carroll County carries meaningfully higher natural disaster exposure than a typical Iowa county.

Is your household prepared for Carroll 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 Carroll County, IA?
Carroll County has a FEMA National Risk Index rating of Relatively Low, placing it in the 58th 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 Carroll County?
Carroll County is evaluated for five major natural hazard types: tornado (85th percentile), flooding (38th percentile), wildfire (29th percentile), earthquake (20th percentile), hurricane (19th percentile). The highest-risk hazard is tornado at the 85th 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 Carroll County risk compare to the Iowa average?
Carroll County's composite risk percentile is 58th, compared to the Iowa state average of 40th percentile. The state's overall risk rating is Very Low. This means Carroll County faces higher natural disaster risk than the typical county in Iowa.
Is Carroll County at risk for tornado?
Yes, Carroll County's tornado risk is at the 85th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Carroll County is at the 38th 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 Carroll County higher risk than average?
Carroll County's composite risk score of 58th percentile is above the Iowa state average of 40th percentile. This elevated risk is driven by tornado exposure (85th 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.