Jefferson County, New York Natural Disaster Risk
FEMA National Risk Index assessment · NY
LowComposite Risk Score
National percentile: 64th
Jefferson County faces low composite natural disaster risk (NRI Risk Index score 64.0, 64th national percentile), driven primarily by winter weather and ice storm exposure. Expected annual loss across all 18 hazard types is $26M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Jefferson County carries a low composite natural disaster risk, with a National Risk Index score of 64.0 out of 100 — placing it in the 64th 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.
Most of Jefferson County's expected losses come from winter weather (heavy snow, blizzards, and hazardous winter conditions) at High risk — $618K in expected annual loss and about 40.21 events per year; ice storm (freezing rain that coats surfaces in heavy, damaging ice) at Medium risk — $502K in expected annual loss and about 1.04 events per year; and strong wind (damaging straight-line winds outside of tornadoes and hurricanes) at Medium risk — $1M in expected annual loss and about 0.77 events per year. Across all hazards, FEMA estimates $26M in expected annual loss for a population of 116K.
Beyond physical exposure, Jefferson County has a low 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 federal record bears this out: Jefferson County has received 21 federal disaster declarations since 1973, including 7 for snowstorm events and 3 for flood events. The most recent was Remnants of Tropical Storm Debby (tropical storm), declared in September 2024.
Among 62 New York counties, Jefferson County ranks #38 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Winter Weather | High | 40.21 / yr | $618K |
| Ice Storm | Medium | 1.04 / yr | $502K |
| Strong Wind | Medium | 0.77 / yr | $1M |
| Riverine Flood | Medium | 0.89 / yr | $19M |
| Earthquake | Low | 0.00 / yr | $952K |
| Cold Wave | Low | 4.84 / yr | $2M |
| Hurricane | Very Low | 0.01 / yr | $111K |
| Landslide | Very Low | 0.42 / yr | $1K |
| Lightning | Low | 25.24 / yr | $222K |
| Heat Wave | Very Low | 1.53 / yr | $179K |
| Wildfire | Very Low | 0.00 / yr | $14K |
| Tornado | Low | 0.13 / yr | $485K |
| Coastal Flood | Very Low | 0.01 / yr | $0 |
| Hail | Very Low | 0.59 / yr | $24K |
| Avalanche | Very Low | 0.00 / yr | $0 |
| Drought | 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 Remnants of Tropical Storm Debby in September 2024. Most frequent causes: Snowstorm (7), Flood (3), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| September 2024 | Tropical Storm | Remnants of Tropical Storm Debby |
| November 2022 | Winter Storm | Severe Winter Storm and Snowstorm |
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| December 2019 | Severe Storm | Severe Storms, Straight-Line Winds, and Flooding |
| November 2017 | Flood | Flooding |
| December 2014 | Snowstorm | Severe Winter Storm, Snowstorm, and Flooding |
| October 2012 | Hurricane | Hurricane Sandy |
| September 2005 | Hurricane | Hurricane Katrina Evacuation |
| August 2004 | Severe Storm | Severe Storms 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 64.0 out of 100, placing it in the Low category and the 64th 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 Winter Weather (High, $618K EAL), Ice Storm (Medium, $502K EAL), Strong Wind (Medium, $1M EAL). These account for most of the county's expected annual losses.
How does Jefferson County compare to other New York counties?
Jefferson County ranks #38 of 62 New York 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 7 for snowstorm events and 3 for flood events. The most recent was Remnants of Tropical Storm Debby, declared in September 2024.
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 $26M EAL is a statistical average, not a guarantee for any specific year or address.