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

Lewis and Clark County Disaster Risk

Lewis and Clark County, Montana

FEMA Risk Rating

Relatively Low

National Percentile

71th

of 3,144 counties

State Rank

#7

of 56 (1 = highest risk)

Flood Risk

65th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Relatively Low

Higher than 65% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Moderate

Higher than 93% of US counties

Tornado

Tornado and severe thunderstorm risk

Very Low

Higher than 9% of US counties

Earthquake

Seismic activity and ground shaking risk

Moderate

Higher than 87% of US counties

Risk Overview

About Natural Disaster Risk in Lewis and Clark County, Montana

Lewis and Clark faces above-average disaster risk

With a composite risk score of 71.25, Lewis and Clark County ranks in the relatively low category—but sits well above the national baseline. This score reflects significant exposure to multiple hazard types, particularly wildfire and earthquake risks that exceed typical American county profiles.

Among Montana's riskiest counties

Lewis and Clark's score of 71.25 far exceeds Montana's state average of 33.31, placing it among the state's most hazard-exposed counties. The county's vulnerability stands out due to concentrated earthquake and wildfire risks that dominate its risk profile.

Higher risk than most neighbors

Lewis and Clark's composite score of 71.25 significantly outpaces nearby Madison County (41.03) and Meagher County (2.80). Only Missoula County, at 77.04, carries comparably elevated disaster risk in the region.

Wildfire and earthquake dominate here

Wildfire risk reaches 92.84 in Lewis and Clark—nearly as high as the state's most fire-prone counties—while earthquake risk scores 86.77, reflecting the county's location in a seismically active zone. Flood risk, at 64.57, also poses meaningful exposure to property damage, particularly along river corridors.

Comprehensive coverage protects your investment

Lewis and Clark residents should prioritize comprehensive homeowners insurance that explicitly covers wildfire damage, often excluded from standard policies. Adding earthquake coverage is essential given the county's 86.77 earthquake risk score; bundled policies typically offer cost savings.

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

Preparedness Guide

What to Prepare for in Lewis and Clark County

Top Hazards by Exposure

  1. #1
    WildfirePrepare
    93th percentile
  2. #2
    EarthquakePrepare
    87th percentile
  3. #3
    FloodPrepare
    65th percentile

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

Risk Advisory: Lewis and Clark County

Risk Verdict

At the 71th percentile nationally, Lewis and Clark County experiences a manageable level of natural hazard risk that falls below the U.S. median. Lewis and Clark County's risk profile calls for targeted preparedness, focusing on the hazard categories that dominate the county's score.

Hazard Breakdown

Wildfire risk is Lewis and Clark County's dominant natural hazard, ranked at the 93th percentile nationally under FEMA's National Risk Index. Earthquake ranks second at the 87th percentile nationally. Additional tracked hazards include flood (65th percentile), tornado (9th percentile).

Preparedness Context

Wildfire ranks as Lewis and Clark County's primary hazard at the 93th percentile nationally. For Lewis and Clark 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. The county's earthquake exposure at the 87th percentile nationally complements the wildfire risk — saturating rain after burn scarring often triggers secondary flood and debris flow events. Lewis and Clark 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

Lewis and Clark County falls 37.9 points above Montana's typical county risk level, which means the hazard environment here is notably more demanding than the state baseline.

Is your household prepared for Lewis and Clark 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 Lewis and Clark County, MT?
Lewis and Clark County has a FEMA National Risk Index rating of Relatively Low, placing it in the 71th 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 Lewis and Clark County?
Lewis and Clark County is evaluated for five major natural hazard types: wildfire (93th percentile), earthquake (87th percentile), flooding (65th percentile), tornado (9th percentile). The highest-risk hazard is wildfire at the 93th 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 Lewis and Clark County risk compare to the Montana average?
Lewis and Clark County's composite risk percentile is 71th, compared to the Montana state average of 33th percentile. The state's overall risk rating is Very Low. This means Lewis and Clark County faces higher natural disaster risk than the typical county in Montana.
Is Lewis and Clark County at risk for wildfire?
Yes, Lewis and Clark County's wildfire risk is at the 93th percentile nationally. This places it in the top quartile for this hazard type. For flooding specifically, Lewis and Clark County is at the 65th 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 Lewis and Clark County higher risk than average?
Lewis and Clark County's composite risk score of 71th percentile is above the Montana state average of 33th percentile. This elevated risk is driven by wildfire exposure (93th percentile), along with earthquake and flooding 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.