Jefferson County, Mississippi Natural Disaster Risk
FEMA National Risk Index assessment · MS
Very LowComposite Risk Score
National percentile: 11th
Jefferson County faces very low composite natural disaster risk (NRI Risk Index score 11.3, 11th national percentile), driven primarily by heat wave and hurricane exposure. Expected annual loss across all 18 hazard types is $3M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
FEMA's National Risk Index rates Jefferson County at very low composite risk, with a National Risk Index score of 11.3 out of 100 — placing it in the 11th national percentile and among the lowest-risk counties in the country. 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 heat wave (prolonged periods of extreme heat that threaten health and infrastructure) at Low risk — $587K in expected annual loss and about 16.47 events per year; hurricane (tropical cyclones bringing extreme wind, rain, and storm surge) at Low risk — $224K in expected annual loss and about 0.10 events per year; and landslide (downhill movement of rock, soil, and debris on unstable slopes) at Low risk — $2K in expected annual loss and about 0.73 events per year. Across all hazards, FEMA estimates $3M in expected annual loss for a population of 7K.
Beyond physical exposure, Jefferson County has a very high 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). That combination — a more vulnerable population with limited resilience — can amplify the human cost of any given event.
The federal record bears this out: Jefferson County has received 26 federal disaster declarations since 1965, including 11 for hurricane events and 6 for severe storm events. The most recent was Severe Winter Storm (winter storm), declared in February 2026.
Among 82 Mississippi counties, Jefferson County ranks #80 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Heat Wave | Low | 16.47 / yr | $587K |
| Hurricane | Low | 0.10 / yr | $224K |
| Landslide | Low | 0.73 / yr | $2K |
| Drought | Low | 11.19 / yr | $108K |
| Hail | Low | 3.14 / yr | $151K |
| Ice Storm | Low | 0.93 / yr | $31K |
| Tornado | Low | 0.54 / yr | $451K |
| Earthquake | Very Low | 0.00 / yr | $42K |
| Strong Wind | Low | 2.71 / yr | $178K |
| Wildfire | Very Low | 0.00 / yr | $8K |
| Cold Wave | Very Low | 0.74 / yr | $129K |
| Lightning | Very Low | 73.73 / yr | $39K |
| Riverine Flood | Very Low | 0.57 / yr | $1M |
| Winter Weather | Very Low | 2.58 / yr | $2K |
| 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 26 federal disaster declarations since 1965, most recently Severe Winter Storm in February 2026. Most frequent causes: Hurricane (11), Severe Storm (6), Flood (3).
| Declared | Type | Disaster |
|---|---|---|
| February 2026 | Winter Storm | Severe Winter Storm |
| January 2026 | Winter Storm | Severe Winter Storm |
| August 2023 | Severe Storm | Severe Storms, Straight-Line Winds, and Tornadoes. |
| October 2021 | Hurricane | Hurricane Ida |
| August 2021 | Hurricane | Hurricane Ida |
| May 2021 | Severe Ice Storm | Severe Winter Storms |
| October 2020 | Hurricane | Hurricane Delta |
| September 2020 | Hurricane | Hurricane Sally |
| August 2020 | Hurricane | Hurricane Marco and Tropical Storm Laura |
| April 2020 | Biological | Covid-19 Pandemic |
Showing the 10 most recent of 26 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 11.3 out of 100, placing it in the Very Low category and the 11th 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 Heat Wave (Low, $587K EAL), Hurricane (Low, $224K EAL), Landslide (Low, $2K EAL). These account for most of the county's expected annual losses.
How does Jefferson County compare to other Mississippi counties?
Jefferson County ranks #80 of 82 Mississippi counties for overall natural disaster risk, with a very low rating.
How many federally declared disasters has Jefferson County had?
FEMA records 26 federal disaster declarations for Jefferson County since 1965, most often 11 for hurricane events and 6 for severe 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. Jefferson County's $3M EAL is a statistical average, not a guarantee for any specific year or address.