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

Plymouth County Disaster Risk

Plymouth County, Iowa

FEMA Risk Rating

Relatively Low

National Percentile

49th

of 3,144 counties

State Rank

#29

of 99 (1 = highest risk)

Flood Risk

45th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Relatively Low

Higher than 45% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Relatively Low

Higher than 71% of US counties

Tornado

Tornado and severe thunderstorm risk

Relatively Low

Higher than 77% of US counties

Earthquake

Seismic activity and ground shaking risk

Very Low

Higher than 14% of US counties

Risk Overview

About Natural Disaster Risk in Plymouth County, Iowa

Plymouth County faces above-average disaster risk

At 49.20, Plymouth County's composite risk score significantly exceeds the national average and earns a Relatively Low rating, reflecting elevated exposure to multiple hazard types. Tornadoes, floods, and wildfires all contribute notably to this profile.

Plymouth ranks among Iowa's riskier counties

Plymouth County's 49.20 score surpasses Iowa's average of 39.68, placing it in the upper tier of the state's risk rankings. The combination of high tornado (77.35), flood (45.23), and wildfire (70.52) risks makes it one of Iowa's more hazard-prone areas.

Plymouth faces distinctly higher risks than neighbors

Neighboring Palo Alto County (15.46) and Pocahontas County (33.05) both carry significantly lower composite risk. Plymouth County's elevated exposure across multiple hazard types sets it apart as the riskier territory in northwest Iowa.

Tornadoes and wildfires drive your risk profile

Tornado risk (77.35) and wildfire risk (70.52) are your two dominant natural hazards, with tornado exposure among the highest in the state. Flood risk (45.23) adds a secondary layer of concern, particularly during spring snow melt and heavy precipitation events.

Invest in comprehensive hazard insurance

Plymouth County residents should maintain robust homeowners insurance covering tornado, hail, and wind damage, with separate flood insurance if in or near a flood zone. Develop a tornado safety plan with a designated shelter and keep emergency supplies stocked year-round.

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

Preparedness Guide

What to Prepare for in Plymouth County

Top Hazards by Exposure

  1. #1
    TornadoPrepare
    77th percentile
  2. #2
    WildfirePrepare
    71th percentile
  3. #3
    FloodPrepare
    45th percentile

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

Risk Advisory: Plymouth County

Risk Verdict

Plymouth County's FEMA risk score places it at the 49th percentile nationally, indicating lower-than-typical exposure for a U.S. county. At the 49th percentile nationally, Plymouth County's natural hazard profile is comparatively favorable — community resilience is reinforced when individual households maintain a reviewed emergency plan.

Hazard Breakdown

Tornado risk is Plymouth County's dominant natural hazard, ranked at the 77th percentile nationally under FEMA's National Risk Index. Wildfire ranks second at the 71th percentile nationally. Additional tracked hazards include flood (45th percentile), earthquake (14th percentile).

Preparedness Context

Tornado exposure at the 77th percentile nationally makes Plymouth County a county where a battery-powered weather radio — not just smartphone apps — is a worthwhile household investment, given that mobile networks often fail during severe storms. The secondary wildfire hazard at the 71th percentile nationally adds seasonal complexity to Plymouth County's preparedness calendar, since wildfire and tornado risk often peak at different points in the year. In Plymouth County, tornado watches indicate favorable atmospheric conditions while warnings mean rotation has been detected — households benefit from understanding this distinction so they shelter immediately on a warning, not after seeking visual confirmation.

Regional Context

The Iowa county average is 9.5 composite points below Plymouth County's score, a gap that reflects the county's elevated position in the state's hazard distribution.

Is your household prepared for Plymouth 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 Plymouth County, IA?
Plymouth County has a FEMA National Risk Index rating of Relatively Low, placing it in the 49th 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 Plymouth County?
Plymouth County is evaluated for five major natural hazard types: tornado (77th percentile), wildfire (71th percentile), flooding (45th percentile), earthquake (14th percentile). The highest-risk hazard is tornado at the 77th 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 Plymouth County risk compare to the Iowa average?
Plymouth County's composite risk percentile is 49th, compared to the Iowa state average of 40th percentile. The state's overall risk rating is Very Low. This means Plymouth County faces higher natural disaster risk than the typical county in Iowa.
Is Plymouth County at risk for tornado?
Yes, Plymouth County's tornado risk is at the 77th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Plymouth County is at the 45th 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 Plymouth County higher risk than average?
Plymouth County's composite risk score of 49th percentile is above the Iowa state average of 40th percentile. This elevated risk is driven by tornado exposure (77th percentile), along with 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.