Ontonagon CountyPower Outage History
2014–2025 · Michigan
Average — typical outage frequency and duration nationally.
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Jul 19, 2020 | 21 hrs | 4,600 (72%) | Thunderstorm Wind |
| Apr 30, 2023 | 9 hrs | 2,518 (39%) | Winter Storm |
| Jul 26, 2023 | 1 hrs | 2,501 (39%) | Unnamed event |
| Nov 26, 2025 | 61 hrs | 2,384 (37%) | Blizzard |
| Nov 19, 2016 | 4 hrs | 2,150 (34%) | Winter Storm |
Over the 12 years from 2014 to 2025, Ontonagon County recorded 348 distinct power outage events, averaging 2.9 hours per event.
The single worst outage on record in Ontonagon County started July 19, 2020 (Thunderstorm Wind), lasting 21 hours and leaving up to 4,600 customers without power (72% of the county) at its peak.
November has historically been the worst month for outages in Ontonagon County, with 46 events recorded during that month across the dataset.
Based on this history, Ontonagon County earns a Reliability Grade of C, placing it in the 47th percentile nationally for grid reliability (higher percentile = more reliable).
Sized for Ontonagon County's outage profile
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Similar counties in Michigan
Counties with the closest reliability grade and national percentile to Ontonagon County.
| County | Grade | National percentile |
|---|---|---|
| Baraga County | C | 48th |
| Chippewa County | C | 48th |
| Ingham County | C | 49th |
| Clinton County | C | 46th |
| Isabella County | C | 49th |
Most reliable counties in Michigan
The top 3 counties in Michigan by reliability grade and percentile.
| County | Grade | National percentile |
|---|---|---|
| Houghton County | B | 77th |
| Grand Traverse County | B | 70th |
| Bay County | B | 61st |
Least reliable counties in Michigan
The bottom 3 counties in Michigan by reliability grade and percentile.
| County | Grade | National percentile |
|---|---|---|
| Ogemaw County | F | 1st |
| Oscoda County | F | 2nd |
| Alcona County | F | 2nd |
Most reliable counties nationally
The top 3 counties nationally by reliability grade and percentile.
| County | State | Grade | National percentile |
|---|---|---|---|
| Clay County | South Dakota | A | 100th |
| Clearwater County | Minnesota | A | 99th |
| Limestone County | Alabama | A | 99th |
Least reliable counties nationally
The bottom 3 counties nationally by reliability grade and percentile.
| County | State | Grade | National percentile |
|---|---|---|---|
| Clay County | West Virginia | F | 0th |
| Lincoln County | West Virginia | F | 0th |
| Cameron Parish | Louisiana | F | 0th |
FAQ
How often does power go out in Ontonagon County?
Between 2014 and 2025, Ontonagon County recorded 348 outage events, averaging 2.9 hours each.
What is Ontonagon County's reliability grade?
Ontonagon County has a Reliability Grade of C, in the 47th national percentile.
What was the worst power outage in Ontonagon County?
The worst outage on record started July 19, 2020 (Thunderstorm Wind), lasting 21 hours and affecting up to 4,600 customers.