Loudoun County, VA
FEMA National Risk Index scores, disaster declarations & hazard data
Loudoun County has experienced 16 federally declared disasters since 1972, most recently Severe Winter Storm in 2026. Its overall natural hazard risk is rated Relatively Low — lower risk than most US counties.
Loudoun County's highest-rated hazards are heat wave, winter weather, and lightning, with its top risk rated "Relatively Moderate" by FEMA's National Risk Index. Recorded storm events have decreased 26% over the past five years compared to the prior five-year period. Community vulnerability is relatively low (11th percentile nationally), indicating stronger recovery capacity than most US counties.
Past disasters & FEMA designations
A federal disaster declaration officially designates a county for FEMA disaster assistance. Loudoun County has been designated in 16 declarations since 1972, covering 6 disaster types including hurricane (5), snowstorm (4), biological (2).
| Year | Type | Event name |
|---|---|---|
| 2026 | Winter Storm | Severe Winter Storm |
| 2020 | Biological | Covid-19 Pandemic |
| 2020 | Biological | Covid-19 |
| 2018 | Hurricane | Hurricane Florence |
| 2016 | Snowstorm | Severe Winter Storm And Snowstorm |
| 2013 | Hurricane | Hurricane Sandy |
| 2013 | Hurricane | Hurricane Sandy |
| 2010 | Snowstorm | Severe Winter Storms And Snowstorms |
| 2005 | Hurricane | Hurricane Katrina Evacuation |
| 2003 | Severe Storm | Severe Winter Storm, Record/Near Record Snowfall, Heavy Rain,Floodind, And Mudslide |
Showing the 10 most recent of 16 total declarations since 1972.
Source: FEMA OpenFEMA Disaster Declarations Summaries. A single disaster can produce more than one record per county. Data current through September 2026.
Risk by hazard type
| Hazard | Risk rating | Risk score | Recorded events | Deaths | Prop. damage |
|---|---|---|---|---|---|
| Wildfire | Very Low | 37.4 | 0 | 0 | — |
| Inland Flooding | Relatively Moderate | 83.9 | 82 | 0 | — |
| Coastal Flooding | Not Applicable | — | 0 | 0 | — |
| Earthquake | Relatively Low | 77.9 | — | — | — |
| Heat Wave | Relatively Moderate | 91.1 | 12 | 0 | — |
| Tornado | Relatively Moderate | 74.7 | 4 | 0 | $6.3M |
| Hurricane | Relatively Low | 80.1 | 0 | 0 | — |
| Hail | Relatively Moderate | 76.5 | 56 | 0 | $110K |
| Strong Wind | Relatively High | 87.4 | 0 | 0 | — |
| Winter Weather | Relatively High | 90.4 | 0 | 0 | — |
| Ice Storm | Very Low | 26.9 | — | — | — |
| Cold Wave | Relatively Low | 24.6 | — | — | — |
| Lightning | Relatively High | 87.8 | 1 | 0 | $336K |
| Drought | Relatively Moderate | 74.1 | 0 | 0 | — |
| Landslide | Very Low | 51.2 | 0 | 0 | — |
| Avalanche | Very Low | 19.7 | — | — | — |
| Tsunami | Not Applicable | — | — | — | — |
| Volcanic Activity | Not Applicable | — | — | — | — |
Scores are 0–100 percentiles relative to all US counties — higher means more exposed, not that a disaster is likely this year. Event counts: NOAA Storm Events 2016–2026; earthquake counts from USGS ComCat (M3.0+, 1996–2026). See the methodology page for details.
Community vulnerability
Loudoun County ranks in the 11th percentile (Very low) for community vulnerability — a measure of how hard disaster impacts tend to hit residents. Higher vulnerability means more displacement, worse health outcomes, and slower recovery after a disaster.
| SVI theme | Percentile | Vulnerability level |
|---|---|---|
| Overall | 11th | Very low |
| Socioeconomic status | 2nd | Very low |
| Household characteristics | 33rd | Low |
| Racial & ethnic minority status | 85th | High |
| Housing type & transportation | 14th | Very low |
Source: CDC/ATSDR Social Vulnerability Index 2022. Percentiles compare counties nationally — higher means more vulnerable relative to other counties. See CDC SVI for full methodology.
Future risk outlook
| Wildfire metric | National percentile | Level |
|---|---|---|
| Burn probability | 26th | Relatively Low |
| Risk to homes | 27th | Relatively Low |
| Buildings in direct exposure zone | 43.8% | — |
NOAA tracked 155 weather events in this county over 2016–2025: 89 in 2016–20 vs 66 in 2021–25 (-26% — frequency decreasing).
Wildfire: USDA Forest Service Wildfire Risk to Communities (RDS-2020-0016-2) — modeled values, not annual forecasts. See wildfirerisk.org. Inland flood and heat projections pending data availability; coastal sea-level projections are available for select coastal counties below — see the data page.
Nearby counties
Frequently asked questions
What natural hazards pose the greatest risk in Loudoun County?
According to the FEMA National Risk Index, the highest-risk hazards in Loudoun County, Virginia are heat wave, winter weather, and lightning. The county's overall natural hazard risk is rated Relatively Low — lower risk than most US counties.
Has Loudoun County received federal disaster declarations?
Yes. Loudoun County has received 16 federal disaster declarations since 1972, including declarations in 2026. The most common disaster type on record is hurricane (5 declarations).
Has Loudoun County had any FEMA disaster declarations in 2024, 2025, or 2026?
Yes. Recent federal disaster declarations for Loudoun County include Severe Winter Storm (2026). See the declarations table above for the full history since 1972.
How does Loudoun County's natural hazard risk compare to nearby counties?
Among neighboring counties, Montgomery County, MD has the highest overall natural hazard risk (Relatively Moderate) and Manassas Park, VA has the lowest (Very Low). Loudoun County is rated Relatively Low overall.
How is Loudoun County's composite disaster risk index calculated?
Loudoun County's composite disaster risk index — officially FEMA's National Risk Index (NRI) — scores every US county on a 0–100 percentile scale across 18 natural hazard types, factoring in expected annual loss, social vulnerability, and community resilience. Loudoun County's composite score of 78 means its overall natural hazard risk is higher than 78% of US counties.