riskbycounty
FEMA NRI 1.19.0Updated Nov 2023 · Coverage 2014–2023Methodology

Jefferson County Disaster Risk

Jefferson County, New York

FEMA Risk Rating

Relatively Low

National Percentile

64th

of 3,144 counties

State Rank

#38

of 62 (1 = highest risk)

Flood Risk

78th

percentile

Hazard Risk Breakdown

Flood

River, coastal, and surface flooding risk

Relatively Low

Higher than 78% of US counties

Wildfire

Wildland and wildland-urban interface fire risk

Very Low

Higher than 28% of US counties

Tornado

Tornado and severe thunderstorm risk

Very Low

Higher than 28% of US counties

Earthquake

Seismic activity and ground shaking risk

Relatively Low

Higher than 71% of US counties

Hurricane

Tropical cyclone and hurricane risk

Relatively Low

Higher than 53% of US counties

Risk Overview

About Natural Disaster Risk in Jefferson County, New York

Jefferson County carries above-average U.S. risk

Jefferson County's composite risk score of 63.96 exceeds the typical American county, positioning residents well above median natural disaster exposure. The county's Lake Ontario shoreline and inland water systems create elevated flood and hurricane risks compared to inland communities.

Below state average but substantially vulnerable

At 63.96, Jefferson County scores about 8% below New York's 69.42 average, placing it in the state's safer-than-average but still notably exposed category. It ranks in the upper-middle tier of New York risk, with roughly one-third of the state's counties carrying lower risk.

Riskier than Franklin and Fulton, safer than Greene

Jefferson County (63.96) significantly exceeds both Franklin (48.85) and Fulton (48.63), falling between Genesee (56.11) and Greene (68.29). Its Lake Ontario exposure and proximity to storm tracks make it notably more vulnerable than purely inland Adirondack counties but less exposed than Hudson Valley communities.

Flooding and earthquakes lead the threats

Flood risk of 77.96 ranks highest, driven by Lake Ontario shoreline exposure and significant river systems crossing the county. Earthquake risk of 71.47 surprises many residents but reflects the county's location near regional seismic activity, while hurricane risk of 53.19 presents seasonal concerns.

Add flood and earthquake coverage now

Jefferson County residents must prioritize flood insurance given the 77.96 risk score, especially those within one mile of Lake Ontario or along major tributaries. Equally important: secure earthquake insurance, as the 71.47 risk score ranks among the state's highest and is often excluded from standard homeowner policies.

Source: FEMA National Risk Index · Narrative reviewed by Evan Brooks, Data Editor

Preparedness Guide

What to Prepare for in Jefferson County

Top Hazards by Exposure

  1. #1
    FloodPrepare
    78th percentile
  2. #2
    EarthquakePrepare
    71th percentile
  3. #3
    HurricanePrepare
    53th percentile

Source: FEMA National Risk Index v1.19.0 · Percentiles are national (3,144 counties)

Risk Advisory: Jefferson County

Risk Verdict

Jefferson County ranks at the 64th percentile nationally for natural disaster risk — below the median for U.S. counties. Residents are encouraged to understand which hazards dominate locally and tailor their preparedness accordingly.

Hazard Breakdown

Flood risk is Jefferson County's dominant natural hazard, ranked at the 78th percentile nationally under FEMA's National Risk Index. Earthquake ranks second at the 71th percentile nationally. Additional tracked hazards include hurricane (53th percentile), wildfire (28th percentile), tornado (28th percentile).

Preparedness Context

Jefferson County sits at the 78th percentile nationally for flood exposure. Knowing your property's flood zone designation — available at FEMA's Flood Map Service Center — is the first step toward understanding actual exposure and insurance options. Alongside flooding, earthquake exposure at the 71th percentile means households benefit from a multi-hazard preparedness plan rather than focusing on flood alone. Regardless of specific hazard, Jefferson County households benefit from a practiced communication plan: a designated out-of-state contact and a pre-agreed evacuation destination established before the season's peak risk period.

Regional Context

A composite score 5.5 points below the New York state average puts Jefferson County in a better-than-typical position relative to neighboring counties.

Is your household prepared for Jefferson County's hazards?

Review FEMA's county-specific preparedness checklists and emergency planning guides.

FEMA Ready Guide →

Frequently Asked Questions

What is the natural disaster risk in Jefferson County, NY?
Jefferson County has a FEMA National Risk Index rating of Relatively Low, placing it in the 64th percentile nationally out of 3,144 counties. This composite score reflects the county's overall exposure to natural hazards including floods, wildfires, tornadoes, earthquakes, and hurricanes, weighted by expected annual loss and social vulnerability.
What types of natural hazards affect Jefferson County?
Jefferson County is evaluated for five major natural hazard types: flooding (78th percentile), earthquake (71th percentile), hurricane (53th percentile), wildfire (28th percentile), tornado (28th percentile). The highest-risk hazard is flooding at the 78th percentile nationally. These scores are derived from FEMA's National Risk Index, which analyzes expected annual loss, social vulnerability, and community resilience for each hazard type.
How does Jefferson County risk compare to the New York average?
Jefferson County's composite risk percentile is 64th, compared to the New York state average of 69th percentile. The state's overall risk rating is Relatively Low. This means Jefferson County faces lower natural disaster risk than the typical county in New York.
Is Jefferson County at risk for flooding?
Yes, Jefferson County's flooding risk is at the 78th percentile nationally. This places it in the top quartile for this hazard type.
How is natural disaster risk measured?
FEMA's National Risk Index (NRI) calculates risk scores for 18 natural hazard types across all U.S. counties and census tracts. The composite score combines Expected Annual Loss (estimated dollar losses from each hazard), Social Vulnerability (demographic factors affecting disaster impact), and Community Resilience (ability to recover). Percentile scores rank each county against all 3,144 U.S. counties, and risk ratings range from Very Low to Very High.
Is Jefferson County a safe place to live?
Jefferson County's composite risk score of 64th percentile is below the New York state average of 69th percentile, indicating relatively lower exposure to natural hazards. However, no county is completely risk-free. The primary hazard type is flooding at the 78th percentile. Residents should still maintain emergency preparedness plans and appropriate insurance coverage.
By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor

Data Source

Risk data sourced from the FEMA National Risk Index (NRI). Risk scores are relative rankings (0–100) across all US counties — not absolute risk measures. Higher scores indicate higher relative risk compared to other counties.

Disclaimer: This data is informational only. It is not financial, insurance, or legal advice. Always consult a qualified professional before making insurance or real estate decisions.