Jefferson County, Kentucky Natural Disaster Risk
FEMA National Risk Index assessment · KY
HighComposite Risk Score
National percentile: 98th
Jefferson County faces high composite natural disaster risk (NRI Risk Index score 98.3, 98th national percentile), driven primarily by tornado and riverine flood exposure. Expected annual loss across all 18 hazard types is $342M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Jefferson County carries a high composite natural disaster risk, with a National Risk Index score of 98.3 out of 100 — placing it in the 98th national percentile and in the upper tier of natural-disaster risk nationally. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Most of Jefferson County's expected losses come from tornado (violently rotating columns of air capable of catastrophic local damage) at Very High risk — $80M in expected annual loss and about 0.28 events per year; riverine flood (rivers and streams overflowing their banks after heavy rain or snowmelt) at High risk — $213M in expected annual loss and about 3.89 events per year; and heat wave (prolonged periods of extreme heat that threaten health and infrastructure) at High risk — $8M in expected annual loss and about 5.63 events per year. Across all hazards, FEMA estimates $342M in expected annual loss for a population of 783K.
Beyond physical exposure, Jefferson County has a medium social vulnerability rating (how susceptible the population is to harm) and a high community resilience rating (its capacity to prepare for and recover from disasters). A less vulnerable population paired with strong resilience helps the community absorb and recover from events.
The county's disaster history tells the same story: Jefferson County has received 25 federal disaster declarations since 1974, including 12 for severe storm events and 4 for flood events. The most recent was Severe Winter Storm (winter storm), declared in January 2026.
Among 120 Kentucky counties, Jefferson County ranks #1 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Tornado | Very High | 0.28 / yr | $80M |
| Riverine Flood | High | 3.89 / yr | $213M |
| Heat Wave | High | 5.63 / yr | $8M |
| Earthquake | Medium | 0.00 / yr | $25M |
| Cold Wave | High | 1.26 / yr | $10M |
| Winter Weather | High | 9.58 / yr | $438K |
| Lightning | High | 52.19 / yr | $1M |
| Strong Wind | High | 6.20 / yr | $2M |
| Hail | Medium | 3.35 / yr | $2M |
| Ice Storm | High | 0.90 / yr | $569K |
| Wildfire | Very Low | 0.00 / yr | $61K |
| Hurricane | Very Low | 0.01 / yr | $20K |
| Landslide | Very Low | 0.20 / yr | $422 |
| Drought | Very Low | 2.26 / yr | $5K |
| 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 25 federal disaster declarations since 1974, most recently Severe Winter Storm in January 2026. Most frequent causes: Severe Storm (12), Flood (4), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| January 2026 | Winter Storm | Severe Winter Storm |
| April 2025 | Severe Storm | Severe Storms, Straight-Line Winds, Tornadoes, Flooding, Landslides, and Mudslides |
| April 2025 | Severe Storm | Severe Storms, Straight-Line Winds, Tornadoes, and Flooding |
| February 2025 | Severe Storm | Severe Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides |
| February 2025 | Severe Storm | Severe Storms, Straight-Line Winds, Flooding, and Landslides |
| May 2024 | Severe Storm | Severe Storms, Straight-Line Winds, Tornadoes, Landslides, and Mudslides |
| April 2023 | Severe Storm | Severe Storms, Straight-Line Winds, Tornadoes, Flooding, Landslides, and Mudslides |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| April 2018 | Flood | Severe Storms, Tornadoes, Flooding, Landslides, and Mudslides |
Showing the 10 most recent of 25 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 98.3 out of 100, placing it in the High category and the 98th 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 Tornado (Very High, $80M EAL), Riverine Flood (High, $213M EAL), Heat Wave (High, $8M EAL). These account for most of the county's expected annual losses.
How does Jefferson County compare to other Kentucky counties?
Jefferson County ranks #1 of 120 Kentucky counties for overall natural disaster risk, with a high rating.
How many federally declared disasters has Jefferson County had?
FEMA records 25 federal disaster declarations for Jefferson County since 1974, most often 12 for severe storm events and 4 for flood events. The most recent was Severe Winter Storm, declared in January 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 $342M EAL is a statistical average, not a guarantee for any specific year or address.