Loudoun County
Virginia — Natural Disaster Risk Assessment
LowComposite Risk Score
National percentile: 78th
Loudoun County faces low composite natural disaster risk (NRI Risk Index score 78.1, 78th national percentile), driven primarily by heat wave and winter weather exposure. Expected annual loss across all 18 hazard types is $61M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Top Hazards
All 18 Hazard Risks
| Heat Wave | Medium | 4.52 / yr | $5M |
| Winter Weather | High | 12.33 / yr | $655K |
| Lightning | High | 38.50 / yr | $2M |
| Strong Wind | High | 7.69 / yr | $3M |
| Riverine Flood | Medium | 3.04 / yr | $37M |
| Hurricane | Low | 0.09 / yr | $3M |
| Earthquake | Low | 0.00 / yr | $2M |
| Hail | Medium | 3.92 / yr | $1M |
| Tornado | Medium | 0.35 / yr | $5M |
| Drought | Medium | 4.06 / yr | $1M |
| Landslide | Very Low | 0.36 / yr | $2K |
| Wildfire | Very Low | 0.00 / yr | $34K |
| Ice Storm | Very Low | 0.58 / yr | $41K |
| Cold Wave | Low | 1.76 / yr | $493K |
| Avalanche | Very Low | 0.01 / yr | $55 |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Frequently Asked Questions
What is the overall natural disaster risk for Loudoun County?
Loudoun County has a composite FEMA National Risk Index score of 78.1 out of 100, placing it in the Low category and the 78th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Loudoun County?
The three highest-rated hazards are Heat Wave (Medium, $5M EAL), Winter Weather (High, $655K EAL), Lightning (High, $2M EAL). These account for most of the county's expected annual losses.
How does Loudoun County compare to other Virginia counties?
Loudoun County ranks #10 of 133 Virginia counties for overall natural disaster risk, with a low rating.
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. Loudoun County's $61M EAL is a statistical average, not a guarantee for any specific year or address.