Chester County, Tennessee Natural Disaster Risk
FEMA National Risk Index assessment · TN
LowComposite Risk Score
National percentile: 44th
Chester County faces low composite natural disaster risk (NRI Risk Index score 44.5, 44th national percentile), driven primarily by earthquake and tornado exposure. Expected annual loss across all 18 hazard types is $13M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Chester County at low composite risk, with a National Risk Index score of 44.5 out of 100 — placing it in the 44th 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 earthquake (ground shaking from sudden movement along geologic faults) at Low risk — $5M in expected annual loss and about 0.01 events per year; tornado (violently rotating columns of air capable of catastrophic local damage) at Medium risk — $2M in expected annual loss and about 0.19 events per year; and cold wave (prolonged spells of dangerously low temperatures) at Medium risk — $2M in expected annual loss and about 1.68 events per year. Across all hazards, FEMA estimates $13M in expected annual loss for a population of 17K.
Beyond physical exposure, Chester County has a medium social vulnerability rating (how susceptible the population is to harm) and a medium 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: Chester County has received 16 federal disaster declarations since 1975, including 9 for severe storm events and 2 for winter storm events. The most recent was Severe Winter Storm (winter storm), declared in February 2026.
Among 95 Tennessee counties, Chester County ranks #62 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Earthquake | Low | 0.01 / yr | $5M |
| Tornado | Medium | 0.19 / yr | $2M |
| Cold Wave | Medium | 1.68 / yr | $2M |
| Landslide | Very Low | 0.64 / yr | $3K |
| Heat Wave | Low | 14.00 / yr | $438K |
| Hurricane | Very Low | 0.05 / yr | $54K |
| Drought | Low | 10.19 / yr | $54K |
| Strong Wind | Low | 2.06 / yr | $360K |
| Lightning | Low | 58.66 / yr | $132K |
| Ice Storm | Very Low | 0.57 / yr | $21K |
| Riverine Flood | Very Low | 0.79 / yr | $2M |
| Wildfire | Very Low | 0.00 / yr | $4K |
| Hail | Very Low | 3.00 / yr | $38K |
| Winter Weather | Very Low | 5.53 / yr | $9K |
| 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
Chester County has received 16 federal disaster declarations since 1975, most recently Severe Winter Storm in February 2026. Most frequent causes: Severe Storm (9), Winter Storm (2), Biological (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 |
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| May 2011 | Severe Storm | Severe Storms, Flooding, Tornadoes, and Straight-Line Winds |
| May 2011 | Severe Storm | Severe Storms, Tornadoes, Straight-Line Winds, and Associated Flooding |
| May 2010 | Severe Storm | Severe Storms, Flooding, Straight-Line Winds, and Tornadoes |
| August 2009 | Severe Storm | Severe Storms and Flooding |
| September 2005 | Hurricane | Hurricane Katrina Evacuation |
Showing the 10 most recent of 16 declarations.
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Chester County?
Chester County has a composite FEMA National Risk Index score of 44.5 out of 100, placing it in the Low category and the 44th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Chester County?
The three highest-rated hazards are Earthquake (Low, $5M EAL), Tornado (Medium, $2M EAL), Cold Wave (Medium, $2M EAL). These account for most of the county's expected annual losses.
How does Chester County compare to other Tennessee counties?
Chester County ranks #62 of 95 Tennessee counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Chester County had?
FEMA records 16 federal disaster declarations for Chester County since 1975, most often 9 for severe storm events and 2 for winter storm 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. Chester County's $13M EAL is a statistical average, not a guarantee for any specific year or address.