riskbycounty
FEMA NRI 1.19.0Updated Nov 2023 · Coverage 2014–2023Methodology

Fairfax County Disaster Risk

Fairfax County, Virginia

FEMA Risk Rating

Relatively High

National Percentile

95th

of 3,144 counties

State Rank

#1

of 133 (1 = highest risk)

Flood Risk

97th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Relatively High

Higher than 97% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Very Low

Higher than 34% of US counties

Tornado

Tornado and severe thunderstorm risk

Relatively Low

Higher than 54% of US counties

Earthquake

Seismic activity and ground shaking risk

Moderate

Higher than 93% of US counties

Hurricane

Tropical cyclone and hurricane risk

Moderate

Higher than 93% of US counties

Risk Overview

About Natural Disaster Risk in Fairfax County, Virginia

Fairfax County faces substantial risk

Fairfax's composite risk score of 94.66 places it in the relatively high category, nearly three times the national average. The county scores exceptionally high across flood (97.01), earthquake (92.81), and hurricane (93.03) risks, indicating broad vulnerability to multiple hazard types.

Virginia's most at-risk county

Fairfax's score of 94.66 vastly exceeds Virginia's state average of 33.27, making it the commonwealth's single most disaster-prone large jurisdiction. This elevated risk reflects the county's dense development, seismic proximity, and susceptibility to flooding and tropical systems.

Fairfax County stands apart in risk

Fairfax's composite score of 94.66 dwarfs neighboring Fairfax city (5.28) and Falls Church city (1.62), highlighting how concentrated disaster risk can be. The county's flood risk of 97.01 is the highest recorded across all Virginia counties analyzed.

Floods, earthquakes, and hurricanes loom large

Fairfax residents face a triple threat: flood risk of 97.01, earthquake risk of 92.81, and hurricane risk of 93.03—all among the highest in the state. Tornado risk (54.48) and wildfire risk (33.97) present secondary but meaningful concerns across the diverse county landscape.

Flood insurance is non-negotiable

With flood risk at 97.01, Fairfax residents must secure federal flood insurance before disaster strikes; standard policies do not cover flooding. Pair flood insurance with comprehensive earthquake and wind coverage, and consider professional seismic retrofitting for older structures in high-risk zones.

Source: FEMA National Risk Index · Narrative reviewed by Evan Brooks, Data Editor

Preparedness Guide

What to Prepare for in Fairfax County

Top Hazards by Exposure

  1. #1
    FloodPrepare
    97th percentile
  2. #2
    HurricanePrepare
    93th percentile
  3. #3
    EarthquakePrepare
    93th percentile

Source: FEMA National Risk Index v1.19.0 · Percentiles are national (3,144 counties)

Risk Advisory: Fairfax County

Risk Verdict

At the 95th percentile nationally, Fairfax County is among the more hazard-exposed counties in the United States. Proactive preparedness — not reactive response — is key to managing life in one of the country's higher-risk counties; Fairfax County residents should plan accordingly.

Hazard Breakdown

Flood risk is Fairfax County's dominant natural hazard, ranked at the 97th percentile nationally under FEMA's National Risk Index. Hurricane ranks second at the 93th percentile nationally. Additional tracked hazards include earthquake (93th percentile), tornado (54th percentile), wildfire (34th percentile).

Preparedness Context

With flood risk ranking at the 97th percentile nationally, Fairfax County residents face one of the most financially damaging hazards without specialized coverage. Flood insurance through the NFIP or a private carrier is worth evaluating regardless of current mortgage requirements. Secondary hurricane exposure at the 93th percentile adds a second preparedness layer; households should review coverage options and alert sign-up for both hazard types. Registering for Fairfax County's county emergency alert system — typically through the county emergency management office's website — ensures households receive early warning when flood events develop faster than forecast.

Regional Context

At 61.4 points above the Virginia state average, Fairfax County carries meaningfully higher natural disaster exposure than a typical Virginia county.

Is your household prepared for Fairfax County's hazards?

Review FEMA's county-specific preparedness checklists and emergency planning guides.

FEMA Ready Guide →

Frequently Asked Questions

What is the natural disaster risk in Fairfax County, VA?
Fairfax County has a FEMA National Risk Index rating of Relatively High, placing it in the 95th percentile nationally out of 3,144 counties. This composite score reflects the county's overall exposure to natural hazards including floods, wildfires, tornadoes, earthquakes, and hurricanes, weighted by expected annual loss and social vulnerability.
What types of natural hazards affect Fairfax County?
Fairfax County is evaluated for five major natural hazard types: flooding (97th percentile), hurricane (93th percentile), earthquake (93th percentile), tornado (54th percentile), wildfire (34th percentile). The highest-risk hazard is flooding at the 97th percentile nationally. These scores are derived from FEMA's National Risk Index, which analyzes expected annual loss, social vulnerability, and community resilience for each hazard type.
How does Fairfax County risk compare to the Virginia average?
Fairfax County's composite risk percentile is 95th, compared to the Virginia state average of 33th percentile. The state's overall risk rating is Very Low. This means Fairfax County faces higher natural disaster risk than the typical county in Virginia.
Is Fairfax County at risk for flooding?
Yes, Fairfax County's flooding risk is at the 97th percentile nationally. This places it in the top quartile for this hazard type.
How is natural disaster risk measured?
FEMA's National Risk Index (NRI) calculates risk scores for 18 natural hazard types across all U.S. counties and census tracts. The composite score combines Expected Annual Loss (estimated dollar losses from each hazard), Social Vulnerability (demographic factors affecting disaster impact), and Community Resilience (ability to recover). Percentile scores rank each county against all 3,144 U.S. counties, and risk ratings range from Very Low to Very High.
Why is Fairfax County higher risk than average?
Fairfax County's composite risk score of 95th percentile is above the Virginia state average of 33th percentile. This elevated risk is driven by flooding exposure (97th percentile), along with hurricane and earthquake and tornado risk. Geographic location, terrain, climate patterns, and proximity to flood zones or fault lines all influence a county's risk profile.
By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor

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.