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

O'Brien County Disaster Risk

O'Brien County, Iowa

FEMA Risk Rating

Very Low

National Percentile

16th

of 3,144 counties

State Rank

#91

of 99 (1 = highest risk)

Flood Risk

19th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Very Low

Higher than 19% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Very Low

Higher than 13% of US counties

Tornado

Tornado and severe thunderstorm risk

Relatively Low

Higher than 49% of US counties

Earthquake

Seismic activity and ground shaking risk

Very Low

Higher than 10% of US counties

Risk Overview

About Natural Disaster Risk in O'Brien County, Iowa

O'Brien County ranks well below average

O'Brien County's composite risk score of 16.41 ranks as Very Low, sitting well below the national average. Your county benefits from geography that limits exposure to major natural disasters.

Among Iowa's safest counties

At 16.41, O'Brien County sits far below Iowa's state average of 39.68. You rank among the state's lowest-risk communities for natural disaster exposure.

Safest in the northwestern region

O'Brien County (16.41) is safer than Osceola County (14.85) and significantly outpaces higher-risk neighbors. Your county's risk level reflects northwestern Iowa's favorable geography for disaster preparedness.

Tornados present primary concern

Tornado risk at 48.73 is O'Brien County's highest hazard, sitting near state average despite your overall low composite score. Flood risk (18.51) remains minimal, while wildfire (12.66) and earthquake (9.76) threats are very limited.

Tornado readiness covers main exposure

With tornado risk at 48.73, ensure your household has access to a safe room, basement shelter, or community tornado plan. Your low overall risk means basic homeowners insurance with standard wind coverage provides solid protection for most scenarios.

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

Preparedness Guide

What to Prepare for in O'Brien County

Top Hazards by Exposure

  1. #1
    TornadoPrepare
    49th percentile
  2. #2
    FloodPrepare
    19th percentile
  3. #3
    WildfirePrepare
    13th percentile

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

Risk Advisory: O'Brien County

Risk Verdict

O'Brien County's overall natural disaster score at the 16th percentile puts it well below the national median for hazard exposure. O'Brien County residents can take confidence from a 16th percentile ranking, but even lower-risk counties benefit from a practiced household communication plan and awareness of the specific hazards listed above.

Hazard Breakdown

Tornado risk is O'Brien County's dominant natural hazard, ranked at the 49th percentile nationally under FEMA's National Risk Index. Flood ranks second at the 19th percentile nationally. Additional tracked hazards include wildfire (13th percentile), earthquake (10th percentile).

Preparedness Context

With tornado ranked at the 49th percentile nationally, O'Brien 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. Alongside tornado exposure, flood at the 19th percentile nationally means O'Brien County households face multi-hazard severe-weather seasons that benefit from a single integrated emergency plan covering both threats. For O'Brien 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

O'Brien County's composite risk score sits 23.3 points below the Iowa county average, reflecting a more favorable hazard environment than the state typical.

Is your household prepared for O'Brien 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 O'Brien County, IA?
O'Brien County has a FEMA National Risk Index rating of Very Low, placing it in the 16th 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 O'Brien County?
O'Brien County is evaluated for five major natural hazard types: tornado (49th percentile), flooding (19th percentile), wildfire (13th percentile), earthquake (10th percentile). The highest-risk hazard is tornado at the 49th 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 O'Brien County risk compare to the Iowa average?
O'Brien County's composite risk percentile is 16th, compared to the Iowa state average of 40th percentile. The state's overall risk rating is Very Low. This means O'Brien County faces lower natural disaster risk than the typical county in Iowa.
Is O'Brien County at risk for tornado?
Yes, O'Brien County's tornado risk is at the 49th percentile nationally. This is below the national median, indicating relatively lower exposure. For flooding specifically, O'Brien County is at the 19th 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 O'Brien County a safe place to live?
O'Brien County's composite risk score of 16th 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 49th percentile. Residents should still maintain emergency preparedness plans and appropriate insurance coverage.
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.