Lake County, Montana Natural Disaster Risk
FEMA National Risk Index assessment · MT
LowComposite Risk Score
National percentile: 68th
Lake County faces low composite natural disaster risk (NRI Risk Index score 67.7, 68th national percentile), driven primarily by winter weather and wildfire exposure. Expected annual loss across all 18 hazard types is $23M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Overall natural disaster risk in Lake County is low, with a National Risk Index score of 67.7 out of 100 — placing it in the 68th national percentile and below the national average 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 High risk — $532K in expected annual loss and about 43.84 events per year; wildfire (uncontrolled fires that spread across wildland and into communities) at Medium risk — $2M in expected annual loss and about 0.00 events per year; and earthquake (ground shaking from sudden movement along geologic faults) at Medium risk — $7M in expected annual loss and about 0.03 events per year. Across all hazards, FEMA estimates $23M in expected annual loss for a population of 31K.
Beyond physical exposure, Lake County has a medium social vulnerability rating (how susceptible the population is to harm) and a medium community resilience rating (its capacity to prepare for and recover from disasters). Both measures sit toward the lower end, indicating relatively modest population sensitivity.
History supports the rating: Lake County has received 8 federal disaster declarations since 2000, including 2 for biological events and 2 for flood events. The most recent was Severe Winter Storm and Straight-Line Winds (straight-line winds), declared in April 2026.
Among 56 Montana counties, Lake County ranks #8 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Winter Weather | High | 43.84 / yr | $532K |
| Wildfire | Medium | 0.00 / yr | $2M |
| Earthquake | Medium | 0.03 / yr | $7M |
| Avalanche | High | 0.23 / yr | $2M |
| Landslide | Medium | 1.40 / yr | $53K |
| Cold Wave | Medium | 4.49 / yr | $5M |
| Ice Storm | Medium | 0.10 / yr | $220K |
| Riverine Flood | Low | 0.43 / yr | $7M |
| Heat Wave | Very Low | 1.44 / yr | $184K |
| Lightning | Low | 20.53 / yr | $125K |
| Drought | Very Low | 24.23 / yr | $8K |
| Strong Wind | Very Low | 0.24 / yr | $75K |
| Hail | Very Low | 0.39 / yr | $31K |
| Tornado | Very Low | 0.03 / yr | $7K |
| 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
Lake County has received 8 federal disaster declarations since 2000, most recently Severe Winter Storm and Straight-Line Winds in April 2026. Most frequent causes: Biological (2), Flood (2), Fire (2).
| Declared | Type | Disaster |
|---|---|---|
| April 2026 | Straight-Line Winds | Severe Winter Storm and Straight-Line Winds |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| May 2019 | Flood | Flooding |
| April 2014 | Flood | Ice Jams and Flooding |
| September 2005 | Hurricane | Hurricane Katrina Evacuation |
| August 2000 | Fire | Wildfires |
| August 2000 | Fire | Mt - Northwestern Zone 1 Fire Complex |
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Lake County?
Lake County has a composite FEMA National Risk Index score of 67.7 out of 100, placing it in the Low category and the 68th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Lake County?
The three highest-rated hazards are Winter Weather (High, $532K EAL), Wildfire (Medium, $2M EAL), Earthquake (Medium, $7M EAL). These account for most of the county's expected annual losses.
How does Lake County compare to other Montana counties?
Lake County ranks #8 of 56 Montana counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Lake County had?
FEMA records 8 federal disaster declarations for Lake County since 2000, most often 2 for biological events and 2 for flood events. The most recent was Severe Winter Storm and Straight-Line Winds, declared in April 2026.
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. Lake County's $23M EAL is a statistical average, not a guarantee for any specific year or address.