Yellowstone County, Montana Natural Disaster Risk
FEMA National Risk Index assessment · MT
MediumComposite Risk Score
National percentile: 84th
Yellowstone County faces medium composite natural disaster risk (NRI Risk Index score 83.6, 84th national percentile), driven primarily by winter weather and cold wave exposure. Expected annual loss across all 18 hazard types is $60M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Yellowstone County carries a medium composite natural disaster risk, with a National Risk Index score of 83.6 out of 100 — placing it in the 84th national percentile and near the national midpoint for natural-disaster risk. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
The county's risk is driven primarily by winter weather (heavy snow, blizzards, and hazardous winter conditions) at Very High risk — $2M in expected annual loss and about 18.28 events per year; cold wave (prolonged spells of dangerously low temperatures) at High risk — $19M in expected annual loss and about 3.55 events per year; and wildfire (uncontrolled fires that spread across wildland and into communities) at Medium risk — $3M in expected annual loss and about 0.00 events per year. Across all hazards, FEMA estimates $60M in expected annual loss for a population of 165K.
Beyond physical exposure, Yellowstone County has a low social vulnerability rating (how susceptible the population is to harm) and a very high community resilience rating (its capacity to prepare for and recover from disasters). A less vulnerable population paired with strong resilience helps the community absorb and recover from events.
History supports the rating: Yellowstone County has received 14 federal disaster declarations since 1978, including 7 for fire events and 2 for flood events. The most recent was Severe Storm and Flooding (flood), declared in June 2022.
Among 56 Montana counties, Yellowstone County ranks #2 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Winter Weather | Very High | 18.28 / yr | $2M |
| Cold Wave | High | 3.55 / yr | $19M |
| Wildfire | Medium | 0.00 / yr | $3M |
| Lightning | High | 31.99 / yr | $1M |
| Riverine Flood | Medium | 1.00 / yr | $29M |
| Hail | Medium | 2.00 / yr | $1M |
| Earthquake | Low | 0.00 / yr | $1M |
| Heat Wave | Low | 2.21 / yr | $1M |
| Landslide | Low | 1.22 / yr | $8K |
| Strong Wind | Medium | 0.85 / yr | $865K |
| Drought | Low | 71.54 / yr | $51K |
| Ice Storm | Low | 0.01 / yr | $47K |
| Tornado | Low | 0.15 / yr | $560K |
| Avalanche | Very Low | 0.01 / yr | $0 |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Disaster History
Yellowstone County has received 14 federal disaster declarations since 1978, most recently Severe Storm and Flooding in June 2022. Most frequent causes: Fire (7), Flood (2), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| June 2022 | Flood | Severe Storm and Flooding |
| July 2021 | Fire | Buffalo Wildfire |
| September 2020 | Fire | Bobcat Fire |
| August 2020 | Fire | Falling Star Fire |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| August 2011 | Fire | Canyon Creek Fire |
| June 2011 | Severe Storm | Severe Storms and Flooding |
| August 2007 | Fire | Ford Road Fire |
| August 2006 | Fire | Emerald Hills Fire |
Showing the 10 most recent of 14 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Yellowstone County?
Yellowstone County has a composite FEMA National Risk Index score of 83.6 out of 100, placing it in the Medium category and the 84th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Yellowstone County?
The three highest-rated hazards are Winter Weather (Very High, $2M EAL), Cold Wave (High, $19M EAL), Wildfire (Medium, $3M EAL). These account for most of the county's expected annual losses.
How does Yellowstone County compare to other Montana counties?
Yellowstone County ranks #2 of 56 Montana counties for overall natural disaster risk, with a medium rating.
How many federally declared disasters has Yellowstone County had?
FEMA records 14 federal disaster declarations for Yellowstone County since 1978, most often 7 for fire events and 2 for flood events. The most recent was Severe Storm and Flooding, declared in June 2022.
What does Expected Annual Loss (EAL) mean?
EAL is FEMA's estimate of average annual dollar losses from natural hazards, calculated from historical event data and exposure models. Yellowstone County's $60M EAL is a statistical average, not a guarantee for any specific year or address.