Adams County, Colorado Natural Disaster Risk
FEMA National Risk Index assessment · CO
MediumComposite Risk Score
National percentile: 91th
Adams County faces medium composite natural disaster risk (NRI Risk Index score 91.2, 91th national percentile), driven primarily by hail and winter weather exposure. Expected annual loss across all 18 hazard types is $131M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Adams County carries a medium composite natural disaster risk, with a National Risk Index score of 91.2 out of 100 — placing it in the 91st 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.
Risk here concentrates in hail (ice stones from severe thunderstorms that damage property and crops) at Very High risk — $44M in expected annual loss and about 8.16 events per year; winter weather (heavy snow, blizzards, and hazardous winter conditions) at Very High risk — $1M in expected annual loss and about 12.43 events per year; and cold wave (prolonged spells of dangerously low temperatures) at High risk — $21M in expected annual loss and about 1.61 events per year. Across all hazards, FEMA estimates $131M in expected annual loss for a population of 519K.
Beyond physical exposure, Adams 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.
History supports the rating: Adams County has received 12 federal disaster declarations since 1965, including 5 for flood events and 2 for biological events. The most recent was Covid-19 Pandemic (biological), declared in March 2020.
Among 64 Colorado counties, Adams County ranks #5 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Hail | Very High | 8.16 / yr | $44M |
| Winter Weather | Very High | 12.43 / yr | $1M |
| Cold Wave | High | 1.61 / yr | $21M |
| Lightning | Very High | 49.94 / yr | $3M |
| Tornado | High | 1.53 / yr | $13M |
| Strong Wind | High | 1.45 / yr | $3M |
| Riverine Flood | Medium | 0.64 / yr | $39M |
| Earthquake | Low | 0.00 / yr | $3M |
| Wildfire | Low | 0.00 / yr | $571K |
| Heat Wave | Low | 0.76 / yr | $2M |
| Volcanic Activity | Very Low | 0.00 / yr | $123 |
| Drought | Low | 25.62 / yr | $470K |
| Ice Storm | Medium | 0.03 / yr | $178K |
| Landslide | Very Low | 0.16 / yr | $761 |
| 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
Adams County has received 12 federal disaster declarations since 1965, most recently Covid-19 Pandemic in March 2020. Most frequent causes: Flood (5), 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 12 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Adams County?
Adams County has a composite FEMA National Risk Index score of 91.2 out of 100, placing it in the Medium category and the 91th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Adams County?
The three highest-rated hazards are Hail (Very High, $44M EAL), Winter Weather (Very High, $1M EAL), Cold Wave (High, $21M EAL). These account for most of the county's expected annual losses.
How does Adams County compare to other Colorado counties?
Adams County ranks #5 of 64 Colorado counties for overall natural disaster risk, with a medium rating.
How many federally declared disasters has Adams County had?
FEMA records 12 federal disaster declarations for Adams County since 1965, most often 5 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. Adams County's $131M EAL is a statistical average, not a guarantee for any specific year or address.