Jefferson County, Tennessee Natural Disaster Risk
FEMA National Risk Index assessment · TN
LowComposite Risk Score
National percentile: 45th
Jefferson County faces low composite natural disaster risk (NRI Risk Index score 44.9, 45th national percentile), driven primarily by landslide and earthquake exposure. Expected annual loss across all 18 hazard types is $12M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Jefferson County at low composite risk, with a National Risk Index score of 44.9 out of 100 — placing it in the 45th national percentile and below the national average for natural-disaster risk. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Risk here concentrates in landslide (downhill movement of rock, soil, and debris on unstable slopes) at Medium risk — $43K in expected annual loss and about 0.82 events per year; earthquake (ground shaking from sudden movement along geologic faults) at Low risk — $2M in expected annual loss and about 0.00 events per year; and lightning (electrical discharges from storms that ignite fires and cause casualties) at Medium risk — $463K in expected annual loss and about 51.91 events per year. Across all hazards, FEMA estimates $12M in expected annual loss for a population of 55K.
Beyond physical exposure, Jefferson County has a medium social vulnerability rating (how susceptible the population is to harm) and a low community resilience rating (its capacity to prepare for and recover from disasters). Both measures sit toward the lower end, indicating relatively modest population sensitivity.
The county's disaster history tells the same story: Jefferson County has received 21 federal disaster declarations since 1973, including 8 for severe storm events and 4 for flood events. The most recent was Severe Winter Storm (winter storm), declared in February 2026.
Among 95 Tennessee counties, Jefferson County ranks #61 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Landslide | Medium | 0.82 / yr | $43K |
| Earthquake | Low | 0.00 / yr | $2M |
| Lightning | Medium | 51.91 / yr | $463K |
| Tornado | Low | 0.08 / yr | $2M |
| Riverine Flood | Low | 0.50 / yr | $7M |
| Ice Storm | Low | 0.22 / yr | $76K |
| Hurricane | Very Low | 0.01 / yr | $33K |
| Strong Wind | Low | 4.63 / yr | $389K |
| Wildfire | Very Low | 0.00 / yr | $27K |
| Cold Wave | Low | 0.58 / yr | $612K |
| Winter Weather | Low | 4.53 / yr | $39K |
| Drought | Low | 18.48 / yr | $30K |
| Hail | Very Low | 2.97 / yr | $83K |
| Heat Wave | Very Low | 0.53 / yr | $64K |
| Avalanche | Very Low | 0.00 / yr | $0 |
| Coastal Flood | Very Low | 0.00 / yr | $0 |
| Tsunami | Very Low | 0.00 / yr | $0 |
| Volcanic Activity | Very Low | 0.00 / yr | $0 |
Disaster History
Jefferson County has received 21 federal disaster declarations since 1973, most recently Severe Winter Storm in February 2026. Most frequent causes: Severe Storm (8), Flood (4), Winter Storm (2).
| Declared | Type | Disaster |
|---|---|---|
| February 2026 | Winter Storm | Severe Winter Storm |
| January 2026 | Winter Storm | Severe Winter Storm |
| April 2025 | Severe Storm | Severe Storms, Straight-Line Winds, Tornadoes, and Flooding |
| October 2024 | Tropical Storm | Tropical Storm Helene |
| September 2023 | Severe Storm | Severe Storms, Straight-Line Winds, and Tornado |
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| April 2019 | Flood | Severe Storms, Flooding, Landslides, and Mudslides |
| June 2017 | Severe Storm | Severe Storms, Straight-Line Winds, and Flooding |
| April 2015 | Severe Ice Storm | Severe Winter Storm and Flooding |
Showing the 10 most recent of 21 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Jefferson County?
Jefferson County has a composite FEMA National Risk Index score of 44.9 out of 100, placing it in the Low category and the 45th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Jefferson County?
The three highest-rated hazards are Landslide (Medium, $43K EAL), Earthquake (Low, $2M EAL), Lightning (Medium, $463K EAL). These account for most of the county's expected annual losses.
How does Jefferson County compare to other Tennessee counties?
Jefferson County ranks #61 of 95 Tennessee counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Jefferson County had?
FEMA records 21 federal disaster declarations for Jefferson County since 1973, most often 8 for severe storm events and 4 for flood events. The most recent was Severe Winter Storm, declared in February 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. Jefferson County's $12M EAL is a statistical average, not a guarantee for any specific year or address.