Summit County, Colorado Natural Disaster Risk
FEMA National Risk Index assessment · CO
LowComposite Risk Score
National percentile: 60th
Summit County faces low composite natural disaster risk (NRI Risk Index score 60.2, 60th national percentile), driven primarily by avalanche and landslide exposure. Expected annual loss across all 18 hazard types is $30M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Overall natural disaster risk in Summit County is low, with a National Risk Index score of 60.2 out of 100 — placing it in the 60th 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.
Risk here concentrates in avalanche (fast-moving snow and debris sliding down steep mountain slopes) at Very High risk — $11M in expected annual loss and about 1.07 events per year; landslide (downhill movement of rock, soil, and debris on unstable slopes) at Medium risk — $137K in expected annual loss and about 0.49 events per year; and lightning (electrical discharges from storms that ignite fires and cause casualties) at Medium risk — $1M in expected annual loss and about 59.95 events per year. Across all hazards, FEMA estimates $30M in expected annual loss for a population of 31K.
Beyond physical exposure, Summit County has a very low 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.
The county's disaster history tells the same story: Summit County has received 6 federal disaster declarations since 1977, including 2 for biological events and 1 for coastal storm events. The most recent was Covid-19 Pandemic (biological), declared in March 2020.
Among 64 Colorado counties, Summit County ranks #16 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Avalanche | Very High | 1.07 / yr | $11M |
| Landslide | Medium | 0.49 / yr | $137K |
| Lightning | Medium | 59.95 / yr | $1M |
| Hail | Medium | 2.33 / yr | $1M |
| Winter Weather | Medium | 36.82 / yr | $221K |
| Riverine Flood | Low | 0.04 / yr | $15M |
| Wildfire | Very Low | 0.00 / yr | $80K |
| Earthquake | Very Low | 0.00 / yr | $326K |
| Volcanic Activity | Very Low | 0.00 / yr | $7 |
| Tornado | Very Low | 0.07 / yr | $382K |
| Ice Storm | Very Low | 0.01 / yr | $22K |
| Strong Wind | Low | 0.42 / yr | $232K |
| Cold Wave | Very Low | 0.34 / yr | $34K |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Drought | Very Low | 37.61 / yr | $0 |
| Heat Wave | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
Disaster History
Summit County has received 6 federal disaster declarations since 1977, most recently Covid-19 Pandemic in March 2020. Most frequent causes: Biological (2), Coastal Storm (1), Snowstorm (1).
| Declared | Type | Disaster |
|---|---|---|
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| September 2005 | Coastal Storm | Hurricane Katrina Evacuation |
| April 2003 | Snowstorm | Snow |
| June 2002 | Fire | Wildfires |
| January 1977 | Drought | Drought |
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Summit County?
Summit County has a composite FEMA National Risk Index score of 60.2 out of 100, placing it in the Low category and the 60th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Summit County?
The three highest-rated hazards are Avalanche (Very High, $11M EAL), Landslide (Medium, $137K EAL), Lightning (Medium, $1M EAL). These account for most of the county's expected annual losses.
How does Summit County compare to other Colorado counties?
Summit County ranks #16 of 64 Colorado counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Summit County had?
FEMA records 6 federal disaster declarations for Summit County since 1977, most often 2 for biological events and 1 for coastal storm events. The most recent was Covid-19 Pandemic, declared in March 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. Summit County's $30M EAL is a statistical average, not a guarantee for any specific year or address.