Lyon County, Kansas Natural Disaster Risk

FEMA National Risk Index assessment · KS

Low

Composite Risk Score

47.6

National percentile: 48th

Lyon County faces low composite natural disaster risk (NRI Risk Index score 47.6, 48th national percentile), driven primarily by ice storm and winter weather exposure. Expected annual loss across all 18 hazard types is $18M.

Source: FEMA National Risk Index v1.20 · Updated December 2025

Risk Overview

Overall natural disaster risk in Lyon County is low, with a National Risk Index score of 47.6 out of 100 — placing it in the 48th 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 ice storm (freezing rain that coats surfaces in heavy, damaging ice) at High risk — $1M in expected annual loss and about 0.75 events per year; winter weather (heavy snow, blizzards, and hazardous winter conditions) at High risk — $437K in expected annual loss and about 11.68 events per year; and wildfire (uncontrolled fires that spread across wildland and into communities) at Low risk — $1M in expected annual loss and about 0.00 events per year. Across all hazards, FEMA estimates $18M in expected annual loss for a population of 32K.

Beyond physical exposure, Lyon 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.

History supports the rating: Lyon County has received 27 federal disaster declarations since 1965, including 17 for severe storm events and 4 for flood events. The most recent was Severe Storms, Straight-Line Winds, Tornadoes, and Flooding (severe storm), declared in September 2025.

Among 105 Kansas counties, Lyon County ranks #22 for overall natural disaster risk.

Expected Annual Loss $18M Annualized county-level EAL
Social Vulnerability Low Population sensitivity
Community Resilience High Capacity to recover
Population 32K Latest estimate

Top Hazards

High $1M/yr
High $437K/yr
Low $1M/yr

All 18 Hazard Risks

Ice Storm High 0.75 / yr$1M
Winter Weather High 11.68 / yr$437K
Wildfire Low 0.00 / yr$1M
Lightning Medium 51.01 / yr$673K
Tornado Medium 0.64 / yr$3M
Hail Low 8.73 / yr$472K
Heat Wave Low 14.42 / yr$679K
Drought Low 20.20 / yr$238K
Strong Wind Medium 6.41 / yr$716K
Cold Wave Low 2.26 / yr$1M
Riverine Flood Low 2.25 / yr$8M
Landslide Very Low 0.14 / yr$772
Earthquake Very Low 0.00 / yr$145K
Avalanche Very Low 0.00 / yr$0
Coastal Flood Very Low 0.00 / yr$0
Hurricane Very Low 0.00 / yr$0
Tsunami Very Low 0.00 / yr$0
Volcanic Activity Very Low 0.00 / yr$0

Disaster History

Lyon County has received 27 federal disaster declarations since 1965, most recently Severe Storms, Straight-Line Winds, Tornadoes, and Flooding in September 2025. Most frequent causes: Severe Storm (17), Flood (4), Biological (2).

DeclaredTypeDisaster
September 2025Severe StormSevere Storms, Straight-Line Winds, Tornadoes, and Flooding
March 2020BiologicalCovid-19 Pandemic
March 2020BiologicalCovid-19
June 2019Severe StormSevere Storms, Straight-Line Winds, Tornadoes, Flooding,Landslides,and Mudslides
May 2019Severe StormTornadoes and Flooding
July 2015Severe StormSevere Storms, Tornadoes, Straight-Line Winds, and Flooding
October 2013Severe StormSevere Storms, Straight-Line Winds, Tornadoes, and Flooding
July 2011Severe StormSevere Storms, Straight-Line Winds, Tornadoes, and Flooding
August 2010Severe StormSevere Storms, Flooding, and Tornadoes
March 2010Severe StormSevere Winter Storms and Snowstorm

Showing the 10 most recent of 27 declarations.

Source: FEMA Disaster Declarations Summaries (OpenFEMA).

Frequently Asked Questions

What is the overall natural disaster risk for Lyon County?

Lyon County has a composite FEMA National Risk Index score of 47.6 out of 100, placing it in the Low category and the 48th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.

What are the top natural hazards in Lyon County?

The three highest-rated hazards are Ice Storm (High, $1M EAL), Winter Weather (High, $437K EAL), Wildfire (Low, $1M EAL). These account for most of the county's expected annual losses.

How does Lyon County compare to other Kansas counties?

Lyon County ranks #22 of 105 Kansas counties for overall natural disaster risk, with a low rating.

How many federally declared disasters has Lyon County had?

FEMA records 27 federal disaster declarations for Lyon County since 1965, most often 17 for severe storm events and 4 for flood events. The most recent was Severe Storms, Straight-Line Winds, Tornadoes, and Flooding, declared in September 2025.

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. Lyon County's $18M EAL is a statistical average, not a guarantee for any specific year or address.