Yukon-Koyukuk Census Area, Alaska Natural Disaster Risk
FEMA National Risk Index assessment · AK
LowComposite Risk Score
National percentile: 62th
Yukon-Koyukuk Census Area faces low composite natural disaster risk (NRI Risk Index score 61.5, 62th national percentile), driven primarily by cold wave and landslide 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 Yukon-Koyukuk Census Area at low composite risk, with a National Risk Index score of 61.5 out of 100 — placing it in the 62nd 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.
Most of Yukon-Koyukuk Census Area's expected losses come from cold wave (prolonged spells of dangerously low temperatures) at High risk — $9M in expected annual loss and about 5.07 events per year; landslide (downhill movement of rock, soil, and debris on unstable slopes) at Medium risk — $68K in expected annual loss and about 3.65 events per year; and wildfire (uncontrolled fires that spread across wildland and into communities) at Medium risk — $1M in expected annual loss and about 0.01 events per year. Across all hazards, FEMA estimates $12M in expected annual loss for a population of 5K.
Beyond physical exposure, Yukon-Koyukuk Census Area has a very high social vulnerability rating (how susceptible the population is to harm) and a very low community resilience rating (its capacity to prepare for and recover from disasters). That combination — a more vulnerable population with limited resilience — can amplify the human cost of any given event.
The federal record bears this out: Yukon-Koyukuk Census Area has received 19 federal disaster declarations since 1986, including 8 for flood events and 3 for fire events. The most recent was Severe Storms, Flooding, and Remnants of Typhoon Halong (flood), declared in October 2025.
Among 30 Alaska counties, Yukon-Koyukuk Census Area ranks #7 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Cold Wave | High | 5.07 / yr | $9M |
| Landslide | Medium | 3.65 / yr | $68K |
| Wildfire | Medium | 0.01 / yr | $1M |
| Avalanche | Medium | 0.03 / yr | $457K |
| Winter Weather | Medium | 24.89 / yr | $113K |
| Earthquake | Low | 0.09 / yr | $647K |
| Volcanic Activity | Very Low | 0.02 / yr | $4 |
| Ice Storm | Very Low | 0.01 / yr | $9K |
| Lightning | Very Low | 32.90 / yr | $26K |
| Riverine Flood | Very Low | 0.01 / yr | $527K |
| Strong Wind | Very Low | 0.00 / yr | $25 |
| Hail | Very Low | 0.00 / yr | $6 |
| Tornado | Very Low | 0.00 / yr | $1 |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Drought | Very Low | 0.00 / 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
Yukon-Koyukuk Census Area has received 19 federal disaster declarations since 1986, most recently Severe Storms, Flooding, and Remnants of Typhoon Halong in October 2025. Most frequent causes: Flood (8), Fire (3), Severe Storm (3).
| Declared | Type | Disaster |
|---|---|---|
| October 2025 | Flood | Severe Storms, Flooding, and Remnants of Typhoon Halong |
| July 2025 | Fire | Nenana Ridge Complex |
| August 2023 | Flood | Flooding |
| June 2022 | Fire | Clear Fire |
| March 2022 | Severe Storm | Severe Winter Storm and Straight-Line Winds |
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| June 2013 | Flood | Flooding |
| June 2009 | Flood | Flooding and Ice Jams |
| September 2008 | Severe Storm | Severe Storms, Flooding, Landslides, and Mudslides |
Showing the 10 most recent of 19 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Yukon-Koyukuk Census Area?
Yukon-Koyukuk Census Area has a composite FEMA National Risk Index score of 61.5 out of 100, placing it in the Low category and the 62th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Yukon-Koyukuk Census Area?
The three highest-rated hazards are Cold Wave (High, $9M EAL), Landslide (Medium, $68K EAL), Wildfire (Medium, $1M EAL). These account for most of the county's expected annual losses.
How does Yukon-Koyukuk Census Area compare to other Alaska counties?
Yukon-Koyukuk Census Area ranks #7 of 30 Alaska counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Yukon-Koyukuk Census Area had?
FEMA records 19 federal disaster declarations for Yukon-Koyukuk Census Area since 1986, most often 8 for flood events and 3 for fire events. The most recent was Severe Storms, Flooding, and Remnants of Typhoon Halong, declared in October 2025.
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. Yukon-Koyukuk Census Area's $12M EAL is a statistical average, not a guarantee for any specific year or address.