Union County, TN
FEMA National Risk Index scores, disaster declarations & hazard data
Union County has experienced 16 federally declared disasters since 1973, most recently Severe Winter Storm in 2026. Its overall natural hazard risk is rated Very Low — among the lowest-risk counties in the country.
Union County's highest-rated hazards are landslide, earthquake, and wildfire, with its top risk rated "Relatively Moderate" by FEMA's National Risk Index.
Past disasters & FEMA designations
A federal disaster declaration officially designates a county for FEMA disaster assistance. Union County has been designated in 16 declarations since 1973, covering 6 disaster types including severe storm (7), flood (3), winter storm (2).
| Year | Type | Event name |
|---|---|---|
| 2026 | Winter Storm | Severe Winter Storm |
| 2026 | Winter Storm | Severe Winter Storm |
| 2025 | Severe Storm | Severe Storms, Straight-Line Winds, Tornadoes, And Flooding |
| 2020 | Biological | Covid-19 Pandemic |
| 2020 | Biological | Covid-19 |
| 2019 | Flood | Severe Storms, Flooding, Landslides, And Mudslides |
| 2011 | Severe Storm | Severe Storms, Tornadoes, And Flooding |
| 2005 | Hurricane | Hurricane Katrina Evacuation |
| 2003 | Severe Storm | Severe Storms And Flooding |
| 2001 | Severe Storm | Severe Storms And Flooding |
Showing the 10 most recent of 16 total declarations since 1973.
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 | 50.4 | 0 | 0 | — |
| Inland Flooding | Very Low | 26 | 5 | 0 | — |
| Coastal Flooding | Not Applicable | — | 0 | 0 | — |
| Earthquake | Relatively Low | 60 | 1 | — | — |
| Heat Wave | Very Low | 11.6 | 0 | 0 | — |
| Tornado | Relatively Low | 35.3 | 0 | 0 | — |
| Hurricane | Very Low | 23 | 0 | 0 | — |
| Hail | Very Low | 26.7 | 3 | 0 | — |
| Strong Wind | Relatively Low | 40.7 | 0 | 0 | — |
| Winter Weather | Relatively Low | 39.8 | 0 | 0 | — |
| Ice Storm | Relatively Low | 28.3 | — | — | — |
| Cold Wave | Relatively Low | 32.5 | — | — | — |
| Lightning | Relatively Low | 37.3 | 0 | 0 | — |
| Drought | No Rating | 0 | 0 | 0 | — |
| Landslide | Relatively Moderate | 88.3 | 0 | 0 | — |
| Avalanche | Not Applicable | — | — | — | — |
| 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
Union County ranks in the 38th percentile (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 | 38th | Low |
| Socioeconomic status | 63rd | Moderate |
| Household characteristics | 40th | Low |
| Racial & ethnic minority status | 5th | Very low |
| Housing type & transportation | 22nd | 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 | 82nd | Very High |
| Risk to homes | 77th | Relatively High |
| Buildings in direct exposure zone | 91.2% | — |
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 Union County?
According to the FEMA National Risk Index, the highest-risk hazards in Union County, Tennessee are landslide, earthquake, and wildfire. The county's overall natural hazard risk is rated Very Low — among the lowest-risk counties in the country.
Has Union County received federal disaster declarations?
Yes. Union County has received 16 federal disaster declarations since 1973, including declarations in 2026. The most common disaster type on record is severe storm (7 declarations).
Has Union County had any FEMA disaster declarations in 2024, 2025, or 2026?
Yes. Recent federal disaster declarations for Union County include Severe Winter Storm (2026), Severe Winter Storm (2026), Severe Storms, Straight-Line Winds, Tornadoes, And Flooding (2025). See the declarations table above for the full history since 1973.
How does Union County's natural hazard risk compare to nearby counties?
Among neighboring counties, Knox County, TN has the highest overall natural hazard risk (Relatively Moderate) and Grainger County, TN has the lowest (Very Low). Union County is rated Very Low overall.
How is Union County's composite disaster risk index calculated?
Union 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. Union County's composite score of 13 means its overall natural hazard risk is higher than 13% of US counties.