Marion CountyPower Outage History
What this grade means
Better than average — fewer or shorter outages than most counties. This county's outage history is better than the national median: recorded outages are less frequent and/or shorter in duration than a typical US county experienced over the same 12-year period. It isn't in the top tier nationally, but its track record points to lower-than-average outage risk.
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Sep 20, 2021 | <1 hr | 9,922 (58%) | Unnamed event |
| May 9, 2023 | <1 hr | 8,518 (50%) | Thunderstorm Wind |
| May 19, 2025 | 7 hrs | 7,277 (43%) | Unnamed event |
| May 30, 2025 | 2 hrs | 4,967 (29%) | Thunderstorm Wind |
| Dec 19, 2025 | 10 hrs | 2,421 (14%) | Unnamed event |
Was There an Outage on a Specific Date?
Pick a date to see whether a power outage was recorded for Marion County, Tennessee that day.
Over the 12 years from 2014 to 2025, Marion County recorded 311 distinct power outage events, averaging 2.9 hours per event.
The single worst outage on record in Marion County started September 20, 2021, lasting less than 1 hour and leaving up to 9,922 customers without power (58% of the county) at its peak.
March has historically been the worst month for outages in Marion County, with 40 events recorded during that month across the dataset.
Based on this history, Marion County earns a Reliability Grade of B, placing it in the 77th percentile nationally for grid reliability (higher percentile = more reliable).
Similar counties in Tennessee
Counties with the closest reliability grade and national percentile to Marion County.
| County | Grade | National percentile |
|---|---|---|
| Marshall County | B | 77th |
| Franklin County | B | 78th |
| Cannon County | B | 78th |
| McMinn County | B | 78th |
| Greene County | B | 76th |
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 Marion County?
Between 2014 and 2025, Marion County recorded 311 outage events, averaging 2.9 hours each.
What is Marion County's reliability grade?
Marion County has a Reliability Grade of B, in the 77th national percentile.
What was the worst power outage in Marion County?
The worst outage on record started September 20, 2021, lasting less than 1 hour and affecting up to 9,922 customers.