Sheridan County Power Outage History
2017–2025 · Wyoming
Top 20% most reliable nationally — infrequent, short outages. How grades are calculated
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Nov 13, 2025 | 7 hrs | 12,017 (65%) | Unnamed event |
| Sep 11, 2022 | 3 hrs | 4,930 (27%) | Unnamed event |
| Feb 16, 2023 | 7 hrs | 3,907 (21%) | Winter Storm |
| Apr 23, 2022 | 5 hrs | 3,262 (18%) | Winter Storm |
| Sep 26, 2023 | 1 hrs | 3,176 (17%) | Unnamed event |
Over the 9 years from 2017 to 2025, Sheridan County recorded 254 distinct power outage events, averaging 2.6 hours per event.
The single worst outage on record in Sheridan County started November 13, 2025, lasting 7 hours and leaving up to 12,017 customers without power (65% of the county) at its peak.
June has historically been the worst month for outages in Sheridan County, with 38 events recorded during that month across the dataset.
Based on this history, Sheridan County earns a Reliability Grade of A, placing it in the 82nd percentile nationally for grid reliability (higher percentile = more reliable).
Sized for Sheridan County's outage profile
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Similar counties in Wyoming
Counties with the closest reliability grade and national percentile to Sheridan County.
| County | Grade | National percentile |
|---|---|---|
| Big Horn County | A | 82nd |
| Sweetwater County | A | 81st |
| Campbell County | B | 80th |
| Natrona County | A | 87th |
| Park County | A | 88th |
FAQ
How often does power go out in Sheridan County?
Between 2017 and 2025, Sheridan County recorded 254 outage events, averaging 2.6 hours each.
What is Sheridan County's reliability grade?
Sheridan County has a Reliability Grade of A, in the 82nd national percentile.
What was the worst power outage in Sheridan County?
The worst outage on record started November 13, 2025, lasting 7 hours and affecting up to 12,017 customers.