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

Marshall County Disaster Risk

Marshall County, Iowa

FEMA Risk Rating

Relatively Low

National Percentile

62th

of 3,144 counties

State Rank

#14

of 99 (1 = highest risk)

Flood Risk

63th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Relatively Low

Higher than 63% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Relatively Low

Higher than 62% of US counties

Tornado

Tornado and severe thunderstorm risk

Moderate

Higher than 83% of US counties

Earthquake

Seismic activity and ground shaking risk

Very Low

Higher than 28% of US counties

Hurricane

Tropical cyclone and hurricane risk

Very Low

Higher than 15% of US counties

Risk Overview

About Natural Disaster Risk in Marshall County, Iowa

Marshall County faces elevated risk profile

Marshall County's composite risk score of 62.47 exceeds Iowa's state average of 39.68 by 57 percent, placing it in the relatively low risk category but well above typical. This elevated positioning reflects significant exposure to multiple hazard types, particularly tornadoes and flooding.

Second-highest risk county in Iowa

Marshall County ranks as Iowa's second-most hazard-prone county, exceeded only by Linn County's exceptional risk profile. This elevated standing places Marshall among the state's most disaster-vulnerable areas and warrants heightened preparedness.

Dramatically riskier than surrounding counties

Marshall's 62.47 score towers above neighboring Linn County (86.70) and dramatically outpaces Marion County (34.35) and other surrounding counties. This concentration of risk is driven by the county's position in Iowa's tornado belt and its exposure to the Cedar and Iowa river systems.

Tornadoes and floods your major concerns

Tornado risk at 82.67 is your most serious threat—nearly 50 percent above state average—making spring severe weather season particularly hazardous. Flood risk of 63.10 comes close behind, with river and creek systems posing regular inundation threats during high-water periods.

Comprehensive coverage is essential here

Your elevated risk profile demands robust homeowners insurance with wind and hail coverage for tornado protection. Strongly consider separate flood insurance if you're within 500 feet of the Cedar River, Iowa River, or other flood-prone waterways; standard policies exclude flood damage entirely.

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

Preparedness Guide

What to Prepare for in Marshall County

Top Hazards by Exposure

  1. #1
    TornadoPrepare
    83th percentile
  2. #2
    FloodPrepare
    63th percentile
  3. #3
    WildfirePrepare
    62th percentile

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

Risk Advisory: Marshall County

Risk Verdict

Natural hazard pressure in Marshall County is below the national midpoint, with a composite score at the 62th percentile. Proactive emergency planning and awareness of the specific hazards driving Marshall County's score can meaningfully reduce household risk.

Hazard Breakdown

Tornado risk is Marshall County's dominant natural hazard, ranked at the 83th percentile nationally under FEMA's National Risk Index. Flood ranks second at the 63th percentile nationally. Additional tracked hazards include wildfire (62th percentile), earthquake (28th percentile), hurricane (15th percentile).

Preparedness Context

With tornado ranked at the 83th percentile nationally, Marshall County sits in a high-exposure zone where the difference between outcomes often comes down to proximity to a reinforced interior shelter and seconds of warning time. Flood is the second hazard driver for Marshall County at the 63th percentile nationally, meaning households should maintain awareness of both severe-weather and flood-specific warning systems. For Marshall County households, safe rooms certified to FEMA 320/361 standards offer the highest protection during a direct tornado hit; households without a safe room should locate the innermost lowest-floor room in their building and practice the route to it before storm season.

Regional Context

Marshall County is 22.8 composite risk points above the Iowa average, indicating that residents face greater natural hazard exposure than most of their in-state neighbors.

Is your household prepared for Marshall 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 Marshall County, IA?
Marshall County has a FEMA National Risk Index rating of Relatively Low, placing it in the 62th 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 Marshall County?
Marshall County is evaluated for five major natural hazard types: tornado (83th percentile), flooding (63th percentile), wildfire (62th percentile), earthquake (28th percentile), hurricane (15th percentile). The highest-risk hazard is tornado at the 83th 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 Marshall County risk compare to the Iowa average?
Marshall County's composite risk percentile is 62th, compared to the Iowa state average of 40th percentile. The state's overall risk rating is Very Low. This means Marshall County faces higher natural disaster risk than the typical county in Iowa.
Is Marshall County at risk for tornado?
Yes, Marshall County's tornado risk is at the 83th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Marshall County is at the 63th 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 Marshall County higher risk than average?
Marshall County's composite risk score of 62th percentile is above the Iowa state average of 40th percentile. This elevated risk is driven by tornado exposure (83th percentile), along with flooding and wildfire 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.