San Diego County Disaster Risk
San Diego County, California
FEMA Risk Rating
Very High
National Percentile
100th
of 3,144 counties
State Rank
#7
of 58 (1 = highest risk)
Flood Risk
100th
percentile
Hazard Risk Breakdown
Flood
River, coastal, and surface flooding risk
Very High
Higher than 100% of US counties
Wildfire
Wildland and wildland-urban interface fire risk
Very High
Higher than 100% of US counties
Tornado
Tornado and severe thunderstorm risk
Relatively Low
Higher than 64% of US counties
Earthquake
Seismic activity and ground shaking risk
Very High
Higher than 100% of US counties
Hurricane
Tropical cyclone and hurricane risk
Very Low
Higher than 8% of US counties
Risk Overview
About Natural Disaster Risk in San Diego County, California
San Diego ranks in nation's highest-risk tier
San Diego County's composite risk score of 99.71 marks it as "Very High" and places it among America's most disaster-prone counties. This score significantly exceeds California's average of 88.72, reflecting severe exposure across multiple hazard categories.
Third-riskiest county in California
San Diego ranks just behind San Bernardino and Riverside in overall state risk, driven by maximal wildfire risk (100.00), near-maximal earthquake risk (99.68), and critical flood risk (99.75). The county's dense population amplifies the impact of these natural disasters.
Far riskier than adjacent Riverside County south
San Diego (99.71) essentially matches Riverside (99.90) and San Bernardino (99.84) in overall risk, though its wildfire exposure is highest in the state at 100.00. Neighboring San Luis Obispo (95.90) faces notably lower threat levels.
Wildfires dominate; earthquakes and floods critical
San Diego's wildfire risk scores 100.00—the absolute maximum and state's highest—with annual fire seasons destroying hundreds of structures and displacing thousands. Earthquake (99.68) and flood (99.75) risks remain severe, creating overlapping disaster scenarios.
Wildfire insurance is non-negotiable in San Diego
San Diego residents face the state's highest wildfire risk and must secure wildfire coverage through their insurer or California's FAIR Plan immediately. Add earthquake coverage and verify flood insurance—this county requires the full suite of disaster protection.
Source: FEMA National Risk Index · Narrative reviewed by Evan Brooks, Data Editor
Preparedness Guide
What to Prepare for in San Diego County
Top Hazards by Exposure
Source: FEMA National Risk Index v1.19.0 · Percentiles are national (3,144 counties)
Risk Advisory: San Diego County
Risk Verdict
Natural disaster risk in San Diego County ranks at the 100th percentile nationally, placing this county among the most hazard-exposed in the country. At this risk level, having a documented household preparedness plan — not just awareness — is the meaningful next step for San Diego County residents.
Hazard Breakdown
Wildfire risk is San Diego County's dominant natural hazard, ranked at the 100th percentile nationally under FEMA's National Risk Index. Flood ranks second at the 100th percentile nationally. Additional tracked hazards include earthquake (100th percentile), tornado (64th percentile), hurricane (8th percentile).
Preparedness Context
San Diego County sits at the 100th percentile for wildfire exposure. Signing up for San Diego County's county emergency alert system and knowing the pre-planned evacuation route before conditions deteriorate are the two highest-value preparedness actions for residents here. The county's flood exposure at the 100th percentile nationally complements the wildfire risk — saturating rain after burn scarring often triggers secondary flood and debris flow events. In San Diego County, wildfire smoke often precedes the flame front by hours or days; households benefit from tracking EPA's AirNow.gov and having HEPA air filtration available as a first line of indoor protection when air quality alerts are issued.
Regional Context
The California county average is 11.0 composite points below San Diego County's score, a gap that reflects the county's elevated position in the state's hazard distribution.
Is your household prepared for San Diego County's hazards?
Review FEMA's county-specific preparedness checklists and emergency planning guides.
Frequently Asked Questions
What is the natural disaster risk in San Diego County, CA?
What types of natural hazards affect San Diego County?
How does San Diego County risk compare to the California average?
Is San Diego County at risk for wildfire?
How is natural disaster risk measured?
Why is San Diego County higher risk than average?
Data Source
Risk data sourced from the FEMA National Risk Index (NRI). Risk scores are relative rankings (0–100) across all US counties — not absolute risk measures. Higher scores indicate higher relative risk compared to other counties.
Disclaimer: This data is informational only. It is not financial, insurance, or legal advice. Always consult a qualified professional before making insurance or real estate decisions.