Humboldt County, California Natural Disaster Risk
FEMA National Risk Index assessment · CA
HighComposite Risk Score
National percentile: 97th
Humboldt County faces high composite natural disaster risk (NRI Risk Index score 96.8, 97th national percentile), driven primarily by landslide and earthquake exposure. Expected annual loss across all 18 hazard types is $189M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Overall natural disaster risk in Humboldt County is high, with a National Risk Index score of 96.8 out of 100 — placing it in the 97th 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.
Risk here concentrates in landslide (downhill movement of rock, soil, and debris on unstable slopes) at High risk — $2M in expected annual loss and about 83.33 events per year; earthquake (ground shaking from sudden movement along geologic faults) at High risk — $94M in expected annual loss and about 0.19 events per year; and wildfire (uncontrolled fires that spread across wildland and into communities) at Medium risk — $3M in expected annual loss and about 0.00 events per year. Across all hazards, FEMA estimates $189M in expected annual loss for a population of 136K.
Beyond physical exposure, Humboldt County has a high 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). That combination — a more vulnerable population with limited resilience — can amplify the human cost of any given event.
History supports the rating: Humboldt County has received 27 federal disaster declarations since 1964, including 12 for flood events and 8 for severe storm events. The most recent was Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides (severe storm), declared in April 2023.
Among 58 California counties, Humboldt County ranks #24 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Landslide | High | 83.33 / yr | $2M |
| Earthquake | High | 0.19 / yr | $94M |
| Wildfire | Medium | 0.00 / yr | $3M |
| Riverine Flood | High | 0.86 / yr | $51M |
| Tsunami | High | 0.23 / yr | $33M |
| Coastal Flood | High | 3.62 / yr | $4M |
| Drought | Medium | 34.37 / yr | $650K |
| Heat Wave | Low | 2.64 / yr | $252K |
| Avalanche | Very Low | 0.01 / yr | $327 |
| Lightning | Low | 5.24 / yr | $93K |
| Hail | Very Low | 0.05 / yr | $40K |
| Winter Weather | Very Low | 13.86 / yr | $6K |
| Tornado | Very Low | 0.03 / yr | $32K |
| Strong Wind | Very Low | 0.01 / yr | $18K |
| Cold Wave | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Ice Storm | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Disaster History
Humboldt County has received 27 federal disaster declarations since 1964, most recently Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides in April 2023. Most frequent causes: Flood (12), Severe Storm (8), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| April 2023 | Severe Storm | Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides |
| March 2023 | Flood | Severe Winter Storms, Flooding, Landslides, and Mudslides |
| January 2023 | Flood | Severe Winter Storms, Flooding, Landslides, and Mudslides |
| January 2023 | Flood | Severe Winter Storms, Flooding, and Mudslides |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| May 2019 | Severe Storm | Severe Winter Storms, Flooding, Landslides, and Mudslides |
| April 2017 | Flood | Severe Winter Storms, Flooding, and Mudslides |
| February 2017 | Severe Storm | Severe Winter Storms, Flooding, and Mudslides |
| February 2006 | Severe Storm | Severe Storms, Flooding, Mudslides, and Landslides |
Showing the 10 most recent of 27 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Humboldt County?
Humboldt County has a composite FEMA National Risk Index score of 96.8 out of 100, placing it in the High category and the 97th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Humboldt County?
The three highest-rated hazards are Landslide (High, $2M EAL), Earthquake (High, $94M EAL), Wildfire (Medium, $3M EAL). These account for most of the county's expected annual losses.
How does Humboldt County compare to other California counties?
Humboldt County ranks #24 of 58 California counties for overall natural disaster risk, with a high rating.
How many federally declared disasters has Humboldt County had?
FEMA records 27 federal disaster declarations for Humboldt County since 1964, most often 12 for flood events and 8 for severe storm events. The most recent was Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides, declared in April 2023.
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. Humboldt County's $189M EAL is a statistical average, not a guarantee for any specific year or address.