Modoc County, California Natural Disaster Risk
FEMA National Risk Index assessment · CA
Very LowComposite Risk Score
National percentile: 40th
Modoc County faces very low composite natural disaster risk (NRI Risk Index score 39.7, 40th national percentile), driven primarily by drought and wildfire exposure. Expected annual loss across all 18 hazard types is $10M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Modoc County at very low composite risk, with a National Risk Index score of 39.7 out of 100 — placing it in the 40th national percentile and among the lowest-risk counties in the country. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Most of Modoc County's expected losses come from drought (extended dry periods that stress water supplies and agriculture) at High risk — $3M in expected annual loss and about 97.66 events per year; wildfire (uncontrolled fires that spread across wildland and into communities) at Medium risk — $2M in expected annual loss and about 0.01 events per year; and volcanic activity (eruptions producing ashfall, lava, and pyroclastic hazards) at Very Low risk — $821 in expected annual loss and about 0.00 events per year. Across all hazards, FEMA estimates $10M in expected annual loss for a population of 9K.
Beyond physical exposure, Modoc County has a 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.
The federal record bears this out: Modoc County has received 17 federal disaster declarations since 1964, including 7 for flood events and 5 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, Modoc County ranks #56 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Drought | High | 97.66 / yr | $3M |
| Wildfire | Medium | 0.01 / yr | $2M |
| Volcanic Activity | Very Low | 0.00 / yr | $821 |
| Earthquake | Low | 0.02 / yr | $583K |
| Riverine Flood | Low | 0.46 / yr | $5M |
| Winter Weather | Low | 16.64 / yr | $29K |
| Landslide | Very Low | 0.86 / yr | $314 |
| Avalanche | Very Low | 0.01 / yr | $89 |
| Heat Wave | Very Low | 3.30 / yr | $106K |
| Lightning | Very Low | 14.49 / yr | $26K |
| Cold Wave | Very Low | 0.09 / yr | $56K |
| Hail | Very Low | 0.05 / yr | $6K |
| Strong Wind | Very Low | 0.03 / yr | $4K |
| Tornado | Very Low | 0.02 / yr | $572 |
| 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
Modoc County has received 17 federal disaster declarations since 1964, most recently Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides in April 2023. Most frequent causes: Flood (7), Severe Storm (5), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| April 2023 | Severe Storm | Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, 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 |
| March 2017 | Flood | Severe Winter Storms, Flooding, and Mudslides |
| August 2014 | Fire | Day Fire |
| September 2005 | Hurricane | Hurricane Katrina Evacuation |
| January 1997 | Severe Storm | Severe Storms, Flooding, Mud and Landslides |
| March 1995 | Severe Storm | Severe Winter Storms, Flooding Landslides, Mud Flow |
Showing the 10 most recent of 17 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Modoc County?
Modoc County has a composite FEMA National Risk Index score of 39.7 out of 100, placing it in the Very Low category and the 40th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Modoc County?
The three highest-rated hazards are Drought (High, $3M EAL), Wildfire (Medium, $2M EAL), Volcanic Activity (Very Low, $821 EAL). These account for most of the county's expected annual losses.
How does Modoc County compare to other California counties?
Modoc County ranks #56 of 58 California counties for overall natural disaster risk, with a very low rating.
How many federally declared disasters has Modoc County had?
FEMA records 17 federal disaster declarations for Modoc County since 1964, most often 7 for flood events and 5 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. Modoc County's $10M EAL is a statistical average, not a guarantee for any specific year or address.