Alger County, Michigan Natural Disaster Risk
FEMA National Risk Index assessment · MI
Very LowComposite Risk Score
National percentile: 10th
Alger County faces very low composite natural disaster risk (NRI Risk Index score 9.6, 10th national percentile), driven primarily by lightning and landslide exposure. Expected annual loss across all 18 hazard types is $4M.
Source: FEMA National Risk Index v1.20 · Updated December 2025
Risk Overview
Overall natural disaster risk in Alger County is very low, with a National Risk Index score of 9.6 out of 100 — placing it in the 10th national percentile and among the lowest-risk counties in the country. The score blends Expected Annual Loss, Social Vulnerability, and Community Resilience across all 18 FEMA hazard types.
Risk here concentrates in lightning (electrical discharges from storms that ignite fires and cause casualties) at High risk — $639K in expected annual loss and about 21.62 events per year; landslide (downhill movement of rock, soil, and debris on unstable slopes) at Low risk — $4K in expected annual loss and about 0.24 events per year; and hail (ice stones from severe thunderstorms that damage property and crops) at Low risk — $302K in expected annual loss and about 0.62 events per year. Across all hazards, FEMA estimates $4M in expected annual loss for a population of 9K.
Beyond physical exposure, Alger County has a high 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). Higher vulnerability is partly offset by strong community resilience and recovery capacity.
The county's disaster history tells the same story: Alger County has received 5 federal disaster declarations since 1977, including 2 for biological events and 1 for hurricane events. The most recent was Covid-19 Pandemic (biological), declared in March 2020.
Among 83 Michigan counties, Alger County ranks #78 for overall natural disaster risk.
Top Hazards
All 18 Hazard Risks
| Lightning | High | 21.62 / yr | $639K |
| Landslide | Low | 0.24 / yr | $4K |
| Hail | Low | 0.62 / yr | $302K |
| Cold Wave | Low | 1.69 / yr | $464K |
| Wildfire | Very Low | 0.00 / yr | $10K |
| Riverine Flood | Very Low | 0.18 / yr | $2M |
| Winter Weather | Very Low | 42.91 / yr | $14K |
| Drought | Very Low | 1.34 / yr | $1K |
| Ice Storm | Very Low | 0.07 / yr | $9K |
| Coastal Flood | Very Low | 0.01 / yr | $0 |
| Strong Wind | Very Low | 0.61 / yr | $99K |
| Tornado | Very Low | 0.11 / yr | $42K |
| Heat Wave | Very Low | 0.16 / yr | $4K |
| Earthquake | Very Low | 0.00 / yr | $800 |
| Avalanche | 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
Alger County has received 5 federal disaster declarations since 1977, most recently Covid-19 Pandemic in March 2020. Most frequent causes: Biological (2), Hurricane (1), Snowstorm (1).
| Declared | Type | Disaster |
|---|---|---|
| March 2020 | Biological | Covid-19 Pandemic |
| March 2020 | Biological | Covid-19 |
| September 2005 | Hurricane | Hurricane Katrina Evacuation |
| January 1978 | Snowstorm | Blizzards & Snowstorms |
| March 1977 | Drought | Drought |
Source: FEMA Disaster Declarations Summaries (OpenFEMA).
Frequently Asked Questions
What is the overall natural disaster risk for Alger County?
Alger County has a composite FEMA National Risk Index score of 9.6 out of 100, placing it in the Very Low category and the 10th national percentile. This combines Expected Annual Loss, Social Vulnerability, and Community Resilience across 18 hazard types.
What are the top natural hazards in Alger County?
The three highest-rated hazards are Lightning (High, $639K EAL), Landslide (Low, $4K EAL), Hail (Low, $302K EAL). These account for most of the county's expected annual losses.
How does Alger County compare to other Michigan counties?
Alger County ranks #78 of 83 Michigan counties for overall natural disaster risk, with a very low rating.
How many federally declared disasters has Alger County had?
FEMA records 5 federal disaster declarations for Alger County since 1977, most often 2 for biological events and 1 for hurricane events. The most recent was Covid-19 Pandemic, declared in March 2020.
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. Alger County's $4M EAL is a statistical average, not a guarantee for any specific year or address.