Lyon County, Nevada Natural Disaster Risk

FEMA National Risk Index assessment · NV

Low

Composite Risk Score

71.4

National percentile: 71th

Lyon County faces low composite natural disaster risk (NRI Risk Index score 71.4, 71th national percentile), driven primarily by wildfire and earthquake exposure. Expected annual loss across all 18 hazard types is $33M.

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

Risk Overview

Lyon County carries a low composite natural disaster risk, with a National Risk Index score of 71.4 out of 100 — placing it in the 71st 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 wildfire (uncontrolled fires that spread across wildland and into communities) at Medium risk — $7M in expected annual loss and about 0.01 events per year; earthquake (ground shaking from sudden movement along geologic faults) at Medium risk — $12M in expected annual loss and about 0.05 events per year; and winter weather (heavy snow, blizzards, and hazardous winter conditions) at High risk — $476K in expected annual loss and about 6.51 events per year. Across all hazards, FEMA estimates $33M in expected annual loss for a population of 59K.

Beyond physical exposure, Lyon County has a low social vulnerability rating (how susceptible the population is to harm) and a very low community resilience rating (its capacity to prepare for and recover from disasters). Both measures sit toward the lower end, indicating relatively modest population sensitivity.

History supports the rating: Lyon County has received 14 federal disaster declarations since 1965, including 4 for severe storm events and 3 for flood events. The most recent was Severe Winter Storms, Flooding, Landslides, and Mudslides (flood), declared in April 2023.

Among 17 Nevada counties, Lyon County ranks #7 for overall natural disaster risk.

Expected Annual Loss $33M Annualized county-level EAL
Social Vulnerability Low Population sensitivity
Community Resilience Very Low Capacity to recover
Population 59K Latest estimate

Top Hazards

Medium $7M/yr
Medium $12M/yr
High $476K/yr

All 18 Hazard Risks

Wildfire Medium 0.01 / yr$7M
Earthquake Medium 0.05 / yr$12M
Winter Weather High 6.51 / yr$476K
Drought Medium 98.89 / yr$570K
Heat Wave Low 4.00 / yr$893K
Riverine Flood Low 1.00 / yr$11M
Lightning Low 18.17 / yr$313K
Volcanic Activity Very Low 0.00 / yr$15
Landslide Very Low 3.97 / yr$473
Ice Storm Low 0.01 / yr$44K
Hail Very Low 0.15 / yr$151K
Strong Wind Low 0.15 / yr$264K
Avalanche Very Low 0.01 / yr$48
Tornado Very Low 0.07 / yr$4K
Coastal Flood Very Low 0.00 / yr$0
Cold Wave Very Low 0.00 / yr$0
Hurricane Very Low 0.00 / yr$0
Tsunami Very Low 0.00 / yr$0

Disaster History

Lyon County has received 14 federal disaster declarations since 1965, most recently Severe Winter Storms, Flooding, Landslides, and Mudslides in April 2023. Most frequent causes: Severe Storm (4), Flood (3), Biological (2).

DeclaredTypeDisaster
April 2023FloodSevere Winter Storms, Flooding, Landslides, and Mudslides
April 2020BiologicalCovid-19 Pandemic
March 2020BiologicalCovid-19
June 2018FireUpper Colony Fire
February 2017Severe StormSevere Winter Storms, Flooding, and Mudslides
January 2008Severe StormSevere Winter Storms and Flooding
June 2006FireLinehan Fire Complex
February 2006Severe StormSevere Storms and Flooding
September 2005HurricaneHurricane Katrina Evacuation
February 2005SnowstormSnow

Showing the 10 most recent of 14 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 71.4 out of 100, placing it in the Low category and the 71th 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 Wildfire (Medium, $7M EAL), Earthquake (Medium, $12M EAL), Winter Weather (High, $476K EAL). These account for most of the county's expected annual losses.

How does Lyon County compare to other Nevada counties?

Lyon County ranks #7 of 17 Nevada counties for overall natural disaster risk, with a low rating.

How many federally declared disasters has Lyon County had?

FEMA records 14 federal disaster declarations for Lyon County since 1965, most often 4 for severe storm events and 3 for flood events. The most recent was Severe Winter Storms, Flooding, Landslides, and Mudslides, declared in April 2023.

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 $33M EAL is a statistical average, not a guarantee for any specific year or address.