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

Sioux County Disaster Risk

Sioux County, North Dakota

FEMA Risk Rating

Relatively Low

National Percentile

62th

of 3,144 counties

State Rank

#4

of 53 (1 = highest risk)

Flood Risk

10th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Very Low

Higher than 10% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Relatively Low

Higher than 81% of US counties

Tornado

Tornado and severe thunderstorm risk

Very Low

Higher than 25% of US counties

Earthquake

Seismic activity and ground shaking risk

Very Low

Higher than 5% of US counties

Risk Overview

About Natural Disaster Risk in Sioux County, North Dakota

Sioux faces notably elevated risk

With a composite risk score of 62.09, Sioux County carries "Relatively Low" but significantly elevated risk compared to most U.S. counties. Your community faces nearly three times the national average exposure to natural disasters.

ND's highest-risk county by far

Sioux County's 62.09 score towers above North Dakota's state average of 22.19, making it the state's most disaster-prone community. This exceptional vulnerability stems primarily from extreme wildfire exposure in the state's northwestern region.

Far riskier than surrounding areas

Sioux County's 62.09 score dwarfs Mountrail County (43.12) to the east and Dunn County (18.77) to the south. Your county faces unique hazard exposure that demands heightened preparedness compared to virtually every neighboring area.

Wildfire dominates your risk profile

Wildfire risk scores an alarming 80.53 in Sioux County—the single highest wildfire exposure in North Dakota. Tornado risk (25.00) and flood risk (9.99) present secondary concerns, but wildfire remains your defining natural hazard.

Wildfire insurance is essential here

Standard homeowners policies often exclude wildfire; verify that your coverage includes this critical peril or purchase a separate rider. Create defensible space around your home, maintain gutters free of debris, and establish an evacuation plan before fire season arrives.

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

Preparedness Guide

What to Prepare for in Sioux County

Top Hazards by Exposure

  1. #1
    WildfirePrepare
    81th percentile
  2. #2
    TornadoPrepare
    25th percentile
  3. #3
    FloodPrepare
    10th percentile

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

Risk Advisory: Sioux County

Risk Verdict

At the 62th percentile nationally, Sioux County experiences a manageable level of natural hazard risk that falls below the U.S. median. Sioux County's risk profile calls for targeted preparedness, focusing on the hazard categories that dominate the county's score.

Hazard Breakdown

Wildfire risk is Sioux County's dominant natural hazard, ranked at the 81th percentile nationally under FEMA's National Risk Index. Tornado ranks second at the 25th percentile nationally. Additional tracked hazards include flood (10th percentile), earthquake (5th percentile).

Preparedness Context

Wildfire ranks as Sioux County's primary hazard at the 81th percentile nationally. For Sioux County households in high-WUI areas, go-bag readiness — the ability to leave within 15 minutes — is more important than shelter-in-place planning for most residential properties. Alongside wildfire, tornado at the 25th percentile nationally means a multi-season preparedness mindset — fire season and flood or storm season often require different household plans. Sioux County county's local emergency management office publishes community-specific wildfire risk assessments and evacuation zone maps; households should review their zone assignment and sign up for zone-specific alerts.

Regional Context

Sioux County falls 39.9 points above North Dakota's typical county risk level, which means the hazard environment here is notably more demanding than the state baseline.

Is your household prepared for Sioux 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 Sioux County, ND?
Sioux 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 Sioux County?
Sioux County is evaluated for five major natural hazard types: wildfire (81th percentile), tornado (25th percentile), flooding (10th percentile), earthquake (5th percentile). The highest-risk hazard is wildfire at the 81th 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 Sioux County risk compare to the North Dakota average?
Sioux County's composite risk percentile is 62th, compared to the North Dakota state average of 22th percentile. The state's overall risk rating is Very Low. This means Sioux County faces higher natural disaster risk than the typical county in North Dakota.
Is Sioux County at risk for wildfire?
Yes, Sioux County's wildfire risk is at the 81th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Sioux County is at the 10th 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 Sioux County higher risk than average?
Sioux County's composite risk score of 62th percentile is above the North Dakota state average of 22th percentile. This elevated risk is driven by wildfire exposure (81th 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.