GeraSure / County Hazard Risk / Yellowstone, MT
Yellowstone County, Montana: Natural Hazard Risk
Gera County Hazard Score: 43.7/100 (Moderate) · FEMA Rating: Relatively Low · Population: 164,624. Based on FEMA National Risk Index (November 2023).
What is the natural hazard risk for Yellowstone County, Montana?
Yellowstone County, Montana has a Gera County Hazard Score (GCHS) of 43.7/100 (Moderate), based on FEMA National Risk Index November 2023 data. Its Expected Annual Loss rank is 61.8/100, social vulnerability rank 30.8/100 and community resilience rank 82.4/100, covering a population of 164,624.
GCHS components — Yellowstone County (November 2023)
| Component | Score / 100 | GCHS Weight | Contribution | What it measures |
|---|---|---|---|---|
| Expected Annual Loss (EAL) | 61.8 | 50% | 30.9 | Estimated annual losses from 18 natural hazards |
| Social Vulnerability (SOVI) | 30.8 | 30% | 9.2 | Community factors affecting disaster response capacity |
| Lack of Resilience (100 − RESL) | 18 | 20% | 3.5 | Resilience score 82.4/100 → inverted so higher = more hazard |
| Gera County Hazard Score (GCHS) | 43.7 | 100% | 43.7 | Moderate — composite index |
GCHS = 0.50 × 61.8 + 0.30 × 30.8 + 0.20 × (100 − 82.4) = 43.7. All inputs are FEMA NRI percentile ranks 0–100.
Yellowstone County Hazard Checker
Explore what the GCHS means for insurance and disaster preparedness in this county.
Gera County Hazard Score (GCHS)
What this means for insurance
A Moderate GCHS suggests mixed risk. Standard policies generally cover you, but flood or earthquake riders may be worth considering.
GCHS is computed by Gera from FEMA NRI data. It is a risk-context index — not an insurance premium quote. Actual premiums depend on your specific property and chosen coverage.
Get property-level risk analysis for Yellowstone County
GeraSure is building detailed property-level hazard risk tools — comparing coverage options specifically for moderate-risk counties like Yellowstone. Join the waitlist to be first.
Yellowstone County hazard risk: frequently asked questions
- What does a GCHS of 43.7/100 mean for Yellowstone County?
- A GCHS of 43.7/100 places Yellowstone County in the "Moderate" band. This is a moderate risk level. Standard insurance policies generally cover the main hazards, but it is worth reviewing coverage for the specific hazard types that affect this area.
- Which natural hazards most affect Yellowstone County?
- The GCHS is computed from FEMA's Expected Annual Loss (EAL) score, which aggregates 18 natural hazard types: hurricanes, riverine flooding, tornadoes, wildfires, earthquakes, hail, drought, winter weather, lightning, strong wind, coastal flooding, cold wave, heat wave, ice storm, landslide, avalanche, tsunami and volcanic activity. Yellowstone County's EAL rank is 61.8/100 — above average across the 18 hazard types.
- What is the FEMA National Risk Index?
- The FEMA National Risk Index (NRI) is a publicly available dataset produced by the US Federal Emergency Management Agency that measures the risk of natural hazards for every US county and census tract. It combines 18 natural hazard types, community social vulnerability and community resilience into a single expected-loss-based risk score. Gera computes the GCHS from the NRI's county-level EAL, SOVI and RESL percentile scores using a documented formula.
- How does Yellowstone County compare to the national average?
- The national mean GCHS across the 480 most-populous US counties is 66.1/100. Yellowstone County scores 43.7/100, which is 22.4 points below the national mean. FEMA's own risk rating for this county is "Relatively Low".
Contains public sector information published by Federal Emergency Management Agency (FEMA) and licensed under the US Government open data, public domain. Source: FEMA National Risk Index (NRI) — Harvard Dataverse (November 2023, published 2024).
Full GCHS formula and verification: Gera County Hazard Score methodology.