Fairfax County, Virginia Natural Disaster Risk

FEMA National Risk Index assessment · VA

High

Composite Risk Score

94.7

National percentile: 95th

Fairfax County faces high composite natural disaster risk (NRI Risk Index score 94.7, 95th national percentile), driven primarily by winter weather and lightning exposure. Expected annual loss across all 18 hazard types is $219M.

Source: FEMA National Risk Index v1.20 · Updated December 2025

Risk Overview

Overall natural disaster risk in Fairfax County is high, with a National Risk Index score of 94.7 out of 100 — placing it in the 95th 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.

Risk here concentrates in winter weather (heavy snow, blizzards, and hazardous winter conditions) at Very High risk — $2M in expected annual loss and about 9.74 events per year; lightning (electrical discharges from storms that ignite fires and cause casualties) at Very High risk — $4M in expected annual loss and about 40.94 events per year; and heat wave (prolonged periods of extreme heat that threaten health and infrastructure) at High risk — $13M in expected annual loss and about 5.88 events per year. Across all hazards, FEMA estimates $219M in expected annual loss for a population of 1.15M.

Beyond physical exposure, Fairfax County has a very low social vulnerability rating (how susceptible the population is to harm) and a medium community resilience rating (its capacity to prepare for and recover from disasters). Both measures sit toward the lower end, indicating relatively modest population sensitivity.

History supports the rating: Fairfax County has received 19 federal disaster declarations since 1972, including 5 for hurricane events and 5 for snowstorm events. The most recent was Severe Winter Storm (winter storm), declared in January 2026.

Among 133 Virginia counties, Fairfax County ranks #1 for overall natural disaster risk.

Expected Annual Loss $219M Annualized county-level EAL
Social Vulnerability Very Low Population sensitivity
Community Resilience Medium Capacity to recover
Population 1.15M Latest estimate

Top Hazards

Very High $2M/yr
Very High $4M/yr
High $13M/yr

All 18 Hazard Risks

Winter Weather Very High 9.74 / yr$2M
Lightning Very High 40.94 / yr$4M
Heat Wave High 5.88 / yr$13M
Riverine Flood High 5.82 / yr$155M
Strong Wind High 7.78 / yr$4M
Hail High 3.91 / yr$4M
Hurricane Medium 0.09 / yr$18M
Earthquake Medium 0.00 / yr$11M
Cold Wave Medium 1.36 / yr$6M
Ice Storm Medium 0.56 / yr$617K
Landslide Low 0.33 / yr$10K
Tornado Low 0.30 / yr$2M
Coastal Flood Low 3.76 / yr$230K
Wildfire Very Low 0.00 / yr$24K
Drought Low 2.17 / yr$47K
Avalanche Very Low 0.00 / yr$0
Tsunami Very Low 0.00 / yr$0
Volcanic Activity Very Low 0.00 / yr$0

Disaster History

Fairfax County has received 19 federal disaster declarations since 1972, most recently Severe Winter Storm in January 2026. Most frequent causes: Hurricane (5), Snowstorm (5), Severe Storm (4).

DeclaredTypeDisaster
January 2026Winter StormSevere Winter Storm
April 2020BiologicalCovid-19 Pandemic
March 2020BiologicalCovid-19
September 2018HurricaneHurricane Florence
March 2016SnowstormSevere Winter Storm and Snowstorm
October 2012HurricaneHurricane Sandy
November 2011Severe StormThe Remnants of Tropical Storm Lee
April 2010SnowstormSevere Winter Storms and Snowstorms
February 2010SnowstormSevere Winter Storm and Snowstorm
July 2006Severe StormSevere Storms, Tornadoes, and Flooding

Showing the 10 most recent of 19 declarations.

Source: FEMA Disaster Declarations Summaries (OpenFEMA).

Frequently Asked Questions

What is the overall natural disaster risk for Fairfax County?

Fairfax County has a composite FEMA National Risk Index score of 94.7 out of 100, placing it in the High category and the 95th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.

What are the top natural hazards in Fairfax County?

The three highest-rated hazards are Winter Weather (Very High, $2M EAL), Lightning (Very High, $4M EAL), Heat Wave (High, $13M EAL). These account for most of the county's expected annual losses.

How does Fairfax County compare to other Virginia counties?

Fairfax County ranks #1 of 133 Virginia counties for overall natural disaster risk, with a high rating.

How many federally declared disasters has Fairfax County had?

FEMA records 19 federal disaster declarations for Fairfax County since 1972, most often 5 for hurricane events and 5 for snowstorm events. The most recent was Severe Winter Storm, declared in January 2026.

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. Fairfax County's $219M EAL is a statistical average, not a guarantee for any specific year or address.