McCormick CountyPower Outage History
What this grade means
Bottom 20% least reliable nationally — frequent and/or long outages. This county ranks in the least reliable fifth of all US counties in our dataset: some combination of frequent outages, long restoration times, or customers affected puts it near the bottom nationally. Backup power is worth prioritizing here rather than treating it as optional.
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Sep 27, 2024 | 353 hrs | 6,369 (60%) | Tropical Storm Helene |
| Sep 11, 2017 | 56 hrs | 5,063 (48%) | High Wind |
| Jul 21, 2023 | 28 hrs | 4,602 (44%) | Thunderstorm Wind |
| Nov 27, 2022 | 2 hrs | 4,335 (41%) | Unnamed event |
| Jun 8, 2025 | 19 hrs | 3,697 (35%) | Thunderstorm Wind |
Was There an Outage on a Specific Date?
Pick a date to see whether a power outage was recorded for McCormick County, South Carolina that day.
Over the 12 years from 2014 to 2025, McCormick County recorded 692 distinct power outage events, averaging 3.1 hours per event.
The single worst outage on record in McCormick County started September 27, 2024 (Tropical Storm Helene), lasting 353 hours and leaving up to 6,369 customers without power (60% of the county) at its peak.
June has historically been the worst month for outages in McCormick County, with 80 events recorded during that month across the dataset.
Based on this history, McCormick County earns a Reliability Grade of F, placing it in the 6th percentile nationally for grid reliability (higher percentile = more reliable).
Similar counties in South Carolina
Counties with the closest reliability grade and national percentile to McCormick County.
| County | Grade | National percentile |
|---|---|---|
| Greenville County | F | 8th |
| Dillon County | F | 12th |
| Spartanburg County | F | 12th |
| Anderson County | F | 14th |
| Marion County | F | 14th |
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 McCormick County?
Between 2014 and 2025, McCormick County recorded 692 outage events, averaging 3.1 hours each.
What is McCormick County's reliability grade?
McCormick County has a Reliability Grade of F, in the 6th national percentile.
What was the worst power outage in McCormick County?
The worst outage on record started September 27, 2024 (Tropical Storm Helene), lasting 353 hours and affecting up to 6,369 customers.