Jefferson 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 |
|---|---|---|---|
| Jun 7, 2024 | 22 hrs | 5,191 (51%) | High Wind |
| Apr 3, 2019 | 3 hrs | 5,030 (49%) | Unnamed event |
| Oct 26, 2021 | <1 hr | 3,630 (35%) | Unnamed event |
| Jun 20, 2025 | 9 hrs | 3,219 (31%) | Unnamed event |
| May 31, 2024 | <1 hr | 3,082 (30%) | High Wind |
Was There an Outage on a Specific Date?
Pick a date to see whether a power outage was recorded for Jefferson County, Idaho that day.
Over the 9 years from 2017 to 2025, Jefferson County recorded 660 distinct power outage events, averaging 2.0 hours per event.
The single worst outage on record in Jefferson County started June 7, 2024 (High Wind), lasting 22 hours and leaving up to 5,191 customers without power (51% of the county) at its peak.
July has historically been the worst month for outages in Jefferson County, with 80 events recorded during that month across the dataset.
Based on this history, Jefferson County earns a Reliability Grade of B, placing it in the 64th percentile nationally for grid reliability (higher percentile = more reliable).
Similar counties in Idaho
Counties with the closest reliability grade and national percentile to Jefferson County.
| County | Grade | National percentile |
|---|---|---|
| Lincoln County | B | 63rd |
| Washington County | B | 68th |
| Elmore County | C | 59th |
| Jerome County | C | 59th |
| Nez Perce County | C | 58th |
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 Jefferson County?
Between 2017 and 2025, Jefferson County recorded 660 outage events, averaging 2.0 hours each.
What is Jefferson County's reliability grade?
Jefferson County has a Reliability Grade of B, in the 64th national percentile.
What was the worst power outage in Jefferson County?
The worst outage on record started June 7, 2024 (High Wind), lasting 22 hours and affecting up to 5,191 customers.