Inyo County, California Natural Disaster Risk
FEMA National Risk Index assessment · CA
LowComposite Risk Score
National percentile: 79th
Inyo County faces low composite natural disaster risk (NRI Risk Index score 79.3, 79th national percentile), driven primarily by heat wave and avalanche exposure. Expected annual loss across all 18 hazard types is $28M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Inyo County carries a low composite natural disaster risk, with a National Risk Index score of 79.3 out of 100 — placing it in the 79th 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.
The county's risk is driven primarily by heat wave (prolonged periods of extreme heat that threaten health and infrastructure) at High risk — $9M in expected annual loss and about 10.39 events per year; avalanche (fast-moving snow and debris sliding down steep mountain slopes) at Very High risk — $3M in expected annual loss and about 0.17 events per year; and earthquake (ground shaking from sudden movement along geologic faults) at Medium risk — $8M in expected annual loss and about 0.08 events per year. Across all hazards, FEMA estimates $28M in expected annual loss for a population of 19K.
Beyond physical exposure, Inyo County has a very high social vulnerability rating (how susceptible the population is to harm) and a 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.
History supports the rating: Inyo County has received 16 federal disaster declarations since 1967, including 7 for flood events and 3 for severe storm events. The most recent was Tropical Storm Hilary (hurricane), declared in November 2023.
Among 58 California counties, Inyo County ranks #51 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Heat Wave | High | 10.39 / yr | $9M |
| Avalanche | Very High | 0.17 / yr | $3M |
| Earthquake | Medium | 0.08 / yr | $8M |
| Wildfire | Low | 0.00 / yr | $429K |
| Landslide | Low | 30.58 / yr | $16K |
| Volcanic Activity | Very Low | 0.00 / yr | $48 |
| Riverine Flood | Low | 4.96 / yr | $7M |
| Winter Weather | Low | 4.55 / yr | $44K |
| Lightning | Low | 15.90 / yr | $88K |
| Drought | Very Low | 152.70 / yr | $6K |
| Tornado | Very Low | 0.10 / yr | $4K |
| Cold Wave | Very Low | 0.00 / yr | $0 |
| Strong Wind | Very Low | 0.06 / yr | $6K |
| Hail | Very Low | 0.02 / yr | $1K |
| Coastal Flood | 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
Inyo County has received 16 federal disaster declarations since 1967, most recently Tropical Storm Hilary in November 2023. Most frequent causes: Flood (7), Severe Storm (3), Hurricane (2).
| Declared | Type | Disaster |
|---|---|---|
| November 2023 | Hurricane | Tropical Storm Hilary |
| 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 |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| March 2017 | Flood | Severe Winter Storms, Flooding, and Mudslides |
| February 2017 | Severe Storm | Severe Winter Storms, Flooding, and Mudslides |
| January 2011 | Flood | Severe Winter Storms, Flooding, and Debris and Mud Flows |
| July 2007 | Fire | Inyo Fire Complex |
Showing the 10 most recent of 16 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Inyo County?
Inyo County has a composite FEMA National Risk Index score of 79.3 out of 100, placing it in the Low category and the 79th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Inyo County?
The three highest-rated hazards are Heat Wave (High, $9M EAL), Avalanche (Very High, $3M EAL), Earthquake (Medium, $8M EAL). These account for most of the county's expected annual losses.
How does Inyo County compare to other California counties?
Inyo County ranks #51 of 58 California counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Inyo County had?
FEMA records 16 federal disaster declarations for Inyo County since 1967, most often 7 for flood events and 3 for severe storm events. The most recent was Tropical Storm Hilary, declared in November 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. Inyo County's $28M EAL is a statistical average, not a guarantee for any specific year or address.