Gregory CountyPower Outage History
2022–2025 · South Dakota
Top 20% most reliable nationally — infrequent, short outages.
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Sep 5, 2025 | <1 hr | 790 (15%) | High Wind |
| Jul 28, 2025 | 24 hrs | 542 (10%) | Excessive Heat |
| May 9, 2025 | <1 hr | 490 (9%) | Unnamed event |
| Dec 16, 2022 | 9 hrs | 300 (6%) | Drought |
| Dec 15, 2022 | 9 hrs | 300 (6%) | Drought |
Over the 4 years from 2022 to 2025, Gregory County recorded 34 distinct power outage events, averaging 2.2 hours per event.
The single worst outage on record in Gregory County started September 5, 2025 (High Wind), lasting less than 1 hour and leaving up to 790 customers without power (15% of the county) at its peak.
September has historically been the worst month for outages in Gregory County, with 6 events recorded during that month across the dataset.
Based on this history, Gregory County earns a Reliability Grade of A, placing it in the 98th percentile nationally for grid reliability (higher percentile = more reliable).
Sized for Gregory County's outage profile
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Outage-prep kit
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Similar counties in South Dakota
Counties with the closest reliability grade and national percentile to Gregory County.
| County | Grade | National percentile |
|---|---|---|
| Hughes County | A | 98th |
| Tripp County | A | 98th |
| Codington County | A | 98th |
| Bennett County | A | 99th |
| Jerauld County | A | 96th |
Most reliable counties in South Dakota
The top 3 counties in South Dakota by reliability grade and percentile.
| County | Grade | National percentile |
|---|---|---|
| Clay County | A | 100th |
| Codington County | A | 98th |
| Tripp County | A | 98th |
Least reliable counties in South Dakota
The bottom 3 counties in South Dakota by reliability grade and percentile.
| County | Grade | National percentile |
|---|---|---|
| Harding County | D | 21st |
| Perkins County | D | 29th |
| Custer County | D | 30th |
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 Gregory County?
Between 2022 and 2025, Gregory County recorded 34 outage events, averaging 2.2 hours each.
What is Gregory County's reliability grade?
Gregory County has a Reliability Grade of A, in the 98th national percentile.
What was the worst power outage in Gregory County?
The worst outage on record started September 5, 2025 (High Wind), lasting less than 1 hour and affecting up to 790 customers.