Yolo County, California Natural Disaster Risk
FEMA National Risk Index assessment · CA
MediumComposite Risk Score
National percentile: 91th
Yolo County faces medium composite natural disaster risk (NRI Risk Index score 91.4, 91th national percentile), driven primarily by drought and earthquake exposure. Expected annual loss across all 18 hazard types is $116M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Overall natural disaster risk in Yolo County is medium, with a National Risk Index score of 91.4 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.
Most of Yolo County's expected losses come from drought (extended dry periods that stress water supplies and agriculture) at Very High risk — $29M in expected annual loss and about 75.35 events per year; earthquake (ground shaking from sudden movement along geologic faults) at Medium risk — $42M in expected annual loss and about 0.07 events per year; and riverine flood (rivers and streams overflowing their banks after heavy rain or snowmelt) at Medium risk — $42M in expected annual loss and about 0.93 events per year. Across all hazards, FEMA estimates $116M in expected annual loss for a population of 216K.
Beyond physical exposure, Yolo County has a 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: Yolo County has received 22 federal disaster declarations since 1964, including 7 for severe storm events and 6 for flood events. The most recent was Severe Winter Storms, Flooding, Landslides, and Mudslides (flood), declared in January 2023.
Among 58 California counties, Yolo County ranks #38 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Drought | Very High | 75.35 / yr | $29M |
| Earthquake | Medium | 0.07 / yr | $42M |
| Riverine Flood | Medium | 0.93 / yr | $42M |
| Wildfire | Low | 0.00 / yr | $988K |
| Landslide | Low | 10.51 / yr | $40K |
| Heat Wave | Low | 7.15 / yr | $2M |
| Volcanic Activity | Very Low | 0.00 / yr | $51 |
| Lightning | Low | 5.84 / yr | $216K |
| Tornado | Very Low | 0.13 / yr | $331K |
| Hail | Very Low | 0.06 / yr | $41K |
| Strong Wind | Very Low | 0.03 / yr | $70K |
| Avalanche | Very Low | 0.01 / yr | $5 |
| Winter Weather | Very Low | 0.07 / yr | $734 |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Cold Wave | Very Low | 0.00 / yr | $0 |
| Hurricane | Very Low | 0.00 / yr | $0 |
| Ice Storm | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
Disaster History
Yolo County has received 22 federal disaster declarations since 1964, most recently Severe Winter Storms, Flooding, Landslides, and Mudslides in January 2023. Most frequent causes: Severe Storm (7), Flood (6), Fire (3).
| Declared | Type | Disaster |
|---|---|---|
| January 2023 | Flood | Severe Winter Storms, Flooding, Landslides, and Mudslides |
| January 2023 | Flood | Severe Winter Storms, Flooding, and Mudslides |
| August 2020 | Fire | Wildfires |
| August 2020 | Fire | Lnu Lightning Fire Complex |
| 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 |
| March 2017 | Flood | Severe Winter Storms, Flooding, and Mudslides |
| February 2017 | Severe Storm | Severe Winter Storms, Flooding, and Mudslides |
Showing the 10 most recent of 22 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Yolo County?
Yolo County has a composite FEMA National Risk Index score of 91.4 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 Yolo County?
The three highest-rated hazards are Drought (Very High, $29M EAL), Earthquake (Medium, $42M EAL), Riverine Flood (Medium, $42M EAL). These account for most of the county's expected annual losses.
How does Yolo County compare to other California counties?
Yolo County ranks #38 of 58 California counties for overall natural disaster risk, with a medium rating.
How many federally declared disasters has Yolo County had?
FEMA records 22 federal disaster declarations for Yolo County since 1964, most often 7 for severe storm events and 6 for flood events. The most recent was Severe Winter Storms, Flooding, Landslides, and Mudslides, declared in January 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. Yolo County's $116M EAL is a statistical average, not a guarantee for any specific year or address.