Arapahoe County, CO
FEMA National Risk Index scores, disaster declarations & hazard data
Arapahoe County has experienced 12 federally declared disasters since 1965, most recently Severe Storms, Flooding, And Tornadoes in 2023. Its overall natural hazard risk is rated Relatively Moderate — near the middle compared to other US counties.
Arapahoe County's highest-rated hazards are hail, lightning, and tornado, with its top risk rated "Very High" by FEMA's National Risk Index. Recorded storm events have increased 33% over the past five years compared to the prior five-year period.
Past disasters & FEMA designations
A federal disaster declaration officially designates a county for FEMA disaster assistance. Arapahoe County has been designated in 12 declarations since 1965, covering 6 disaster types including flood (5), biological (2), snowstorm (2).
| Year | Type | Event name |
|---|---|---|
| 2023 | Flood | Severe Storms, Flooding, And Tornadoes |
| 2020 | Biological | Covid-19 Pandemic |
| 2020 | Biological | Covid-19 |
| 2013 | Flood | Severe Storms, Flooding, Landslides, And Mudslides |
| 2013 | Flood | Severe Storms, Flooding, Landslides, And Mudslides |
| 2007 | Snowstorm | Snow |
| 2005 | Coastal Storm | Hurricane Katrina Evacuation |
| 2003 | Snowstorm | Snow |
| 2002 | Fire | Wildfires |
| 1973 | Flood | Heavy Rains, Snowmelt And Flooding |
Showing the 10 most recent of 12 total declarations since 1965.
Source: FEMA OpenFEMA Disaster Declarations Summaries. A single disaster can produce more than one record per county. Data current through September 2026.
Risk by hazard type
| Hazard | Risk rating | Risk score | Recorded events | Deaths | Prop. damage |
|---|---|---|---|---|---|
| Wildfire | Relatively Low | 84.7 | 0 | 0 | — |
| Inland Flooding | Relatively Moderate | 92.5 | 7 | 2 | $660K |
| Coastal Flooding | Not Applicable | — | 0 | 0 | — |
| Earthquake | Relatively Low | 85.5 | — | — | — |
| Heat Wave | Relatively Low | 68.6 | 0 | 0 | — |
| Tornado | Relatively High | 97.2 | 11 | 0 | $200K |
| Hurricane | Not Applicable | — | 0 | 0 | — |
| Hail | Very High | 99.8 | 158 | 0 | $276.4M |
| Strong Wind | Relatively High | 95.1 | 0 | 0 | — |
| Winter Weather | Relatively High | 91.1 | 0 | 0 | — |
| Ice Storm | Very Low | 11.4 | — | — | — |
| Cold Wave | Relatively High | 91.1 | — | — | — |
| Lightning | Very High | 98.4 | 1 | 0 | $50K |
| Drought | Relatively Low | 44.6 | 0 | 0 | — |
| Landslide | Very Low | 50.5 | 0 | 0 | — |
| Avalanche | Not Applicable | — | — | — | — |
| Tsunami | Not Applicable | — | — | — | — |
| Volcanic Activity | Very Low | 73 | — | — | — |
Scores are 0–100 percentiles relative to all US counties — higher means more exposed, not that a disaster is likely this year. Event counts: NOAA Storm Events 2016–2026; earthquake counts from USGS ComCat (M3.0+, 1996–2026). See the methodology page for details.
Community vulnerability
Arapahoe County ranks in the 47th percentile (Low) for community vulnerability — a measure of how hard disaster impacts tend to hit residents. Higher vulnerability means more displacement, worse health outcomes, and slower recovery after a disaster.
| SVI theme | Percentile | Vulnerability level |
|---|---|---|
| Overall | 47th | Low |
| Socioeconomic status | 41st | Low |
| Household characteristics | 40th | Low |
| Racial & ethnic minority status | 80th | High |
| Housing type & transportation | 41st | Low |
Source: CDC/ATSDR Social Vulnerability Index 2022. Percentiles compare counties nationally — higher means more vulnerable relative to other counties. See CDC SVI for full methodology.
Future risk outlook
| Wildfire metric | National percentile | Level |
|---|---|---|
| Burn probability | 73rd | Relatively High |
| Risk to homes | 73rd | Relatively High |
| Buildings in direct exposure zone | 13.3% | — |
NOAA tracked 177 weather events in this county over 2016–2025: 76 in 2016–20 vs 101 in 2021–25 (+33% — frequency increasing).
Wildfire: USDA Forest Service Wildfire Risk to Communities (RDS-2020-0016-2) — modeled values, not annual forecasts. See wildfirerisk.org. Inland flood and heat projections pending data availability; coastal sea-level projections are available for select coastal counties below — see the data page.
Nearby counties
Frequently asked questions
What natural hazards pose the greatest risk in Arapahoe County?
According to the FEMA National Risk Index, the highest-risk hazards in Arapahoe County, Colorado are hail, lightning, and tornado. The county's overall natural hazard risk is rated Relatively Moderate — near the middle compared to other US counties.
Has Arapahoe County received federal disaster declarations?
Yes. Arapahoe County has received 12 federal disaster declarations since 1965, including declarations in 2023. The most common disaster type on record is flood (5 declarations).
Has Arapahoe County had any FEMA disaster declarations in 2024, 2025, or 2026?
No federal disaster declarations have been recorded for Arapahoe County since the start of 2024. Its most recent declaration on record is Severe Storms, Flooding, And Tornadoes in 2023.
How does Arapahoe County's natural hazard risk compare to nearby counties?
Among neighboring counties, Denver County, CO has the highest overall natural hazard risk (Relatively High) and Broomfield County, CO has the lowest (Very Low). Arapahoe County is rated Relatively Moderate overall.
How is Arapahoe County's composite disaster risk index calculated?
Arapahoe County's composite disaster risk index — officially FEMA's National Risk Index (NRI) — scores every US county on a 0–100 percentile scale across 18 natural hazard types, factoring in expected annual loss, social vulnerability, and community resilience. Arapahoe County's composite score of 94 means its overall natural hazard risk is higher than 94% of US counties.