Stephenson CountyPower Outage History
What this grade means
Average — typical outage frequency and duration nationally. This county sits in the middle of the national distribution — its outage frequency and duration over the past 12 years are close to the nationwide median, neither notably better nor worse than most other US counties. A typical amount of backup-power preparedness is reasonable here.
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Feb 22, 2023 | 71 hrs | 6,972 (29%) | Winter Storm |
| Jul 16, 2024 | 69 hrs | 6,053 (25%) | Thunderstorm Wind |
| Jul 20, 2017 | 42 hrs | 5,080 (21%) | Thunderstorm Wind |
| Mar 26, 2019 | 6 hrs | 4,937 (21%) | Flood |
| Jun 29, 2017 | 20 hrs | 4,868 (20%) | Hail |
Was There an Outage on a Specific Date?
Pick a date to see whether a power outage was recorded for Stephenson County, Illinois that day.
Over the 12 years from 2014 to 2025, Stephenson County recorded 487 distinct power outage events, averaging 3.1 hours per event.
The single worst outage on record in Stephenson County started February 22, 2023 (Winter Storm), lasting 71 hours and leaving up to 6,972 customers without power (29% of the county) at its peak.
July has historically been the worst month for outages in Stephenson County, with 70 events recorded during that month across the dataset.
Based on this history, Stephenson County earns a Reliability Grade of C, placing it in the 57th percentile nationally for grid reliability (higher percentile = more reliable).
Similar counties in Illinois
Counties with the closest reliability grade and national percentile to Stephenson County.
| County | Grade | National percentile |
|---|---|---|
| St. Clair County | C | 58th |
| Marion County | C | 59th |
| Lawrence County | C | 60th |
| Woodford County | C | 60th |
| Alexander County | B | 60th |
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 Stephenson County?
Between 2014 and 2025, Stephenson County recorded 487 outage events, averaging 3.1 hours each.
What is Stephenson County's reliability grade?
Stephenson County has a Reliability Grade of C, in the 57th national percentile.
What was the worst power outage in Stephenson County?
The worst outage on record started February 22, 2023 (Winter Storm), lasting 71 hours and affecting up to 6,972 customers.