Teton County, Idaho Natural Disaster Risk
FEMA National Risk Index assessment · ID
Very LowComposite Risk Score
National percentile: 29th
Teton County faces very low composite natural disaster risk (NRI Risk Index score 29.5, 29th national percentile), driven primarily by avalanche and wildfire exposure. Expected annual loss across all 18 hazard types is $12M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Teton County at very low composite risk, with a National Risk Index score of 29.5 out of 100 — placing it in the 29th national percentile and among the lowest-risk counties in the country. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Most of Teton County's expected losses come from avalanche (fast-moving snow and debris sliding down steep mountain slopes) at High risk — $2M in expected annual loss and about 0.17 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 Low risk — $2M in expected annual loss and about 0.02 events per year. Across all hazards, FEMA estimates $12M in expected annual loss for a population of 12K.
Beyond physical exposure, Teton County has a very low social vulnerability rating (how susceptible the population is to harm) and a low community resilience rating (its capacity to prepare for and recover from disasters). Both measures sit toward the lower end, indicating relatively modest population sensitivity.
The federal record bears this out: Teton County has received 3 federal disaster declarations since 2005, including 2 for biological events and 1 for hurricane events. The most recent was Covid-19 Pandemic (biological), declared in April 2020.
Among 44 Idaho counties, Teton County ranks #28 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Avalanche | High | 0.17 / yr | $2M |
| Wildfire | Medium | 0.00 / yr | $2M |
| Earthquake | Low | 0.02 / yr | $2M |
| Lightning | Medium | 41.11 / yr | $611K |
| Landslide | Low | 0.47 / yr | $7K |
| Winter Weather | Medium | 29.81 / yr | $134K |
| Volcanic Activity | Very Low | 0.00 / yr | $13 |
| Cold Wave | Low | 1.90 / yr | $956K |
| Riverine Flood | Very Low | 0.18 / yr | $4M |
| Hail | Very Low | 0.29 / yr | $98K |
| Drought | Very Low | 28.76 / yr | $1K |
| Tornado | Very Low | 0.02 / yr | $92K |
| Heat Wave | Very Low | 0.19 / yr | $21K |
| Ice Storm | Very Low | 0.01 / yr | $5K |
| Strong Wind | Very Low | 0.45 / yr | $43K |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
Disaster History
Teton County has received 3 federal disaster declarations since 2005, most recently Covid-19 Pandemic in April 2020. Most frequent causes: Biological (2), Hurricane (1).
| Declared | Type | Disaster |
|---|---|---|
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| September 2005 | Hurricane | Hurricane Katrina |
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Teton County?
Teton County has a composite FEMA National Risk Index score of 29.5 out of 100, placing it in the Very Low category and the 29th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Teton County?
The three highest-rated hazards are Avalanche (High, $2M EAL), Wildfire (Medium, $2M EAL), Earthquake (Low, $2M EAL). These account for most of the county's expected annual losses.
How does Teton County compare to other Idaho counties?
Teton County ranks #28 of 44 Idaho counties for overall natural disaster risk, with a very low rating.
How many federally declared disasters has Teton County had?
FEMA records 3 federal disaster declarations for Teton County since 2005, most often 2 for biological events and 1 for hurricane events. The most recent was Covid-19 Pandemic, declared in April 2020.
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. Teton County's $12M EAL is a statistical average, not a guarantee for any specific year or address.