Denver County, Colorado Natural Disaster Risk
FEMA National Risk Index assessment · CO
HighComposite Risk Score
National percentile: 95th
Denver County faces high composite natural disaster risk (NRI Risk Index score 95.2, 95th national percentile), driven primarily by hail and lightning exposure. Expected annual loss across all 18 hazard types is $222M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Denver County carries a high composite natural disaster risk, with a National Risk Index score of 95.2 out of 100 — placing it in the 95th national percentile and in the upper tier of natural-disaster risk nationally. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Most of Denver County's expected losses come from hail (ice stones from severe thunderstorms that damage property and crops) at Very High risk — $72M in expected annual loss and about 8.29 events per year; lightning (electrical discharges from storms that ignite fires and cause casualties) at Very High risk — $4M in expected annual loss and about 52.24 events per year; and tornado (violently rotating columns of air capable of catastrophic local damage) at High risk — $28M in expected annual loss and about 0.16 events per year. Across all hazards, FEMA estimates $222M in expected annual loss for a population of 715K.
Beyond physical exposure, Denver County has a very low social vulnerability rating (how susceptible the population is to harm) and a 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.
The federal record bears this out: Denver County has received 11 federal disaster declarations since 1965, including 4 for flood events and 2 for biological events. The most recent was Covid-19 Pandemic (biological), declared in March 2020.
Among 64 Colorado counties, Denver County ranks #1 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Hail | Very High | 8.29 / yr | $72M |
| Lightning | Very High | 52.24 / yr | $4M |
| Tornado | High | 0.16 / yr | $28M |
| Strong Wind | High | 1.19 / yr | $4M |
| Riverine Flood | High | 0.82 / yr | $94M |
| Cold Wave | High | 1.26 / yr | $10M |
| Winter Weather | High | 13.74 / yr | $562K |
| Earthquake | Medium | 0.00 / yr | $7M |
| Landslide | Medium | 0.03 / yr | $49K |
| Volcanic Activity | Very Low | 0.00 / yr | $170 |
| Heat Wave | Low | 1.00 / yr | $1M |
| Wildfire | Very Low | 0.00 / yr | $105K |
| Drought | Very Low | 21.00 / yr | $7K |
| Ice Storm | Very Low | 0.02 / yr | $8K |
| Avalanche | Very Low | 0.00 / yr | $0 |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
Disaster History
Denver County has received 11 federal disaster declarations since 1965, most recently Covid-19 Pandemic in March 2020. Most frequent causes: Flood (4), Biological (2), Snowstorm (2).
| Declared | Type | Disaster |
|---|---|---|
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| July 2015 | Flood | Severe Storms, Tornadoes, Flooding, Landslides, and Mudslides |
| September 2013 | Flood | Severe Storms, Flooding, Landslides, and Mudslides |
| September 2013 | Flood | Severe Storms, Flooding, Landslides, and Mudslides |
| January 2007 | Snowstorm | Snow |
| September 2005 | Coastal Storm | Hurricane Katrina Evacuation |
| April 2003 | Snowstorm | Snow |
| June 2002 | Fire | Wildfires |
| May 1973 | Flood | Heavy Rains, Snowmelt and Flooding |
Showing the 10 most recent of 11 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Denver County?
Denver County has a composite FEMA National Risk Index score of 95.2 out of 100, placing it in the High category and the 95th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Denver County?
The three highest-rated hazards are Hail (Very High, $72M EAL), Lightning (Very High, $4M EAL), Tornado (High, $28M EAL). These account for most of the county's expected annual losses.
How does Denver County compare to other Colorado counties?
Denver County ranks #1 of 64 Colorado counties for overall natural disaster risk, with a high rating.
How many federally declared disasters has Denver County had?
FEMA records 11 federal disaster declarations for Denver County since 1965, most often 4 for flood events and 2 for biological 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. Denver County's $222M EAL is a statistical average, not a guarantee for any specific year or address.