Lyon County, Minnesota Natural Disaster Risk
FEMA National Risk Index assessment · MN
LowComposite Risk Score
National percentile: 43th
Lyon County faces low composite natural disaster risk (NRI Risk Index score 43.5, 43th national percentile), driven primarily by winter weather and drought exposure. Expected annual loss across all 18 hazard types is $21M.
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 43.5 out of 100 — placing it in the 43rd 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.
The county's risk is driven primarily by winter weather (heavy snow, blizzards, and hazardous winter conditions) at High risk — $479K in expected annual loss and about 21.53 events per year; drought (extended dry periods that stress water supplies and agriculture) at Medium risk — $1M in expected annual loss and about 11.35 events per year; and cold wave (prolonged spells of dangerously low temperatures) at Medium risk — $4M in expected annual loss and about 12.58 events per year. Across all hazards, FEMA estimates $21M in expected annual loss for a population of 25K.
Beyond physical exposure, Lyon County has a very 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 18 federal disaster declarations since 1969, including 7 for severe storm events and 7 for flood events. The most recent was Severe Storms, Straight-Line Winds, Tornadoes, and Flooding (severe storm), declared in August 2022.
Among 87 Minnesota counties, Lyon County ranks #43 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Winter Weather | High | 21.53 / yr | $479K |
| Drought | Medium | 11.35 / yr | $1M |
| Cold Wave | Medium | 12.58 / yr | $4M |
| Hail | Low | 4.15 / yr | $761K |
| Riverine Flood | Low | 1.46 / yr | $13M |
| Ice Storm | Low | 0.56 / yr | $148K |
| Tornado | Low | 0.47 / yr | $1M |
| Landslide | Very Low | 0.09 / yr | $946 |
| Heat Wave | Very Low | 3.47 / yr | $264K |
| Strong Wind | Low | 2.95 / yr | $515K |
| Wildfire | Very Low | 0.00 / yr | $9K |
| Earthquake | Very Low | 0.00 / yr | $27K |
| Lightning | Very Low | 35.97 / yr | $22K |
| 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 18 federal disaster declarations since 1969, most recently Severe Storms, Straight-Line Winds, Tornadoes, and Flooding in August 2022. Most frequent causes: Severe Storm (7), Flood (7), Biological (2).
| Declared | Type | Disaster |
|---|---|---|
| August 2022 | Severe Storm | Severe Storms, Straight-Line Winds, Tornadoes, and Flooding |
| April 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| June 2019 | Flood | Severe Winter Storm, Straight-Line Winds, and Flooding |
| September 2018 | Flood | Severe Storms, Tornadoes, Straight-Line Winds, and Flooding |
| July 2014 | Flood | Severe Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides |
| July 2011 | Severe Storm | Severe Storms, Flooding, and Tornadoes |
| May 2011 | Flood | Severe Storms and Flooding |
| October 2010 | Severe Storm | Severe Storms and Flooding |
| March 2010 | Flood | Flooding |
Showing the 10 most recent of 18 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 43.5 out of 100, placing it in the Low category and the 43th 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 Winter Weather (High, $479K EAL), Drought (Medium, $1M EAL), Cold Wave (Medium, $4M EAL). These account for most of the county's expected annual losses.
How does Lyon County compare to other Minnesota counties?
Lyon County ranks #43 of 87 Minnesota counties for overall natural disaster risk, with a low rating.
How many federally declared disasters has Lyon County had?
FEMA records 18 federal disaster declarations for Lyon County since 1969, most often 7 for severe storm events and 7 for flood events. The most recent was Severe Storms, Straight-Line Winds, Tornadoes, and Flooding, declared in August 2022.
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 $21M EAL is a statistical average, not a guarantee for any specific year or address.