San Luis Obispo County, California Natural Disaster Risk
FEMA National Risk Index assessment · CA
HighComposite Risk Score
National percentile: 96th
San Luis Obispo County faces high composite natural disaster risk (NRI Risk Index score 95.9, 96th national percentile), driven primarily by drought and landslide exposure. Expected annual loss across all 18 hazard types is $214M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates San Luis Obispo County at high composite risk, with a National Risk Index score of 95.9 out of 100 — placing it in the 96th 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.
Most of San Luis Obispo 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 89.59 events per year; landslide (downhill movement of rock, soil, and debris on unstable slopes) at High risk — $2M in expected annual loss and about 128.71 events per year; and wildfire (uncontrolled fires that spread across wildland and into communities) at High risk — $17M in expected annual loss and about 0.01 events per year. Across all hazards, FEMA estimates $214M in expected annual loss for a population of 280K.
Beyond physical exposure, San Luis Obispo County has a low social vulnerability rating (how susceptible the population is to harm) and a very 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: San Luis Obispo County has received 28 federal disaster declarations since 1967, including 10 for flood events and 8 for severe storm events. The most recent was Severe Winter Storms, Tornadoes, Flooding, Landslides, and Mudslides (severe storm), declared in April 2024.
Among 58 California counties, San Luis Obispo County ranks #28 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Drought | Very High | 89.59 / yr | $29M |
| Landslide | High | 128.71 / yr | $2M |
| Wildfire | High | 0.01 / yr | $17M |
| Earthquake | Medium | 0.11 / yr | $50M |
| Riverine Flood | High | 0.64 / yr | $110M |
| Heat Wave | Low | 8.54 / yr | $2M |
| Tsunami | Low | 0.38 / yr | $3M |
| Coastal Flood | Low | 3.10 / yr | $136K |
| Lightning | Low | 3.22 / yr | $96K |
| Hail | Very Low | 0.05 / yr | $48K |
| Tornado | Very Low | 0.09 / yr | $29K |
| Avalanche | Very Low | 0.01 / yr | $2 |
| Strong Wind | Very Low | 0.02 / yr | $36K |
| Winter Weather | Very Low | 1.05 / yr | $2K |
| 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
San Luis Obispo County has received 28 federal disaster declarations since 1967, most recently Severe Winter Storms, Tornadoes, Flooding, Landslides, and Mudslides in April 2024. Most frequent causes: Flood (10), Severe Storm (8), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| April 2024 | Severe Storm | Severe Winter Storms, Tornadoes, Flooding, Landslides, and Mudslides |
| 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 |
| 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 28 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for San Luis Obispo County?
San Luis Obispo County has a composite FEMA National Risk Index score of 95.9 out of 100, placing it in the High category and the 96th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in San Luis Obispo County?
The three highest-rated hazards are Drought (Very High, $29M EAL), Landslide (High, $2M EAL), Wildfire (High, $17M EAL). These account for most of the county's expected annual losses.
How does San Luis Obispo County compare to other California counties?
San Luis Obispo County ranks #28 of 58 California counties for overall natural disaster risk, with a high rating.
How many federally declared disasters has San Luis Obispo County had?
FEMA records 28 federal disaster declarations for San Luis Obispo County since 1967, most often 10 for flood events and 8 for severe storm events. The most recent was Severe Winter Storms, Tornadoes, Flooding, Landslides, and Mudslides, declared in April 2024.
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. San Luis Obispo County's $214M EAL is a statistical average, not a guarantee for any specific year or address.