Williamson County Power Outage History
2014–2025 · Illinois
Better than average — fewer or shorter outages than most counties. How grades are calculated
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Jan 5, 2025 | 85 hrs | 10,894 (22%) | Ice Storm |
| May 27, 2024 | 16 hrs | 8,670 (17%) | Hail |
| Mar 24, 2019 | 2 hrs | 7,719 (15%) | Unnamed event |
| Jun 29, 2018 | 14 hrs | 7,504 (15%) | Thunderstorm Wind |
| Jul 10, 2021 | 5 hrs | 6,630 (13%) | Thunderstorm Wind |
Over the 12 years from 2014 to 2025, Williamson County recorded 365 distinct power outage events, averaging 2.4 hours per event.
The single worst outage on record in Williamson County started January 5, 2025 (Ice Storm), lasting 85 hours and leaving up to 10,894 customers without power (22% of the county) at its peak.
July has historically been the worst month for outages in Williamson County, with 47 events recorded during that month across the dataset.
Based on this history, Williamson County earns a Reliability Grade of B, placing it in the 72nd percentile nationally for grid reliability (higher percentile = more reliable).
Sized for Williamson County's outage profile
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Outage-prep kit
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Similar counties in Illinois
Counties with the closest reliability grade and national percentile to Williamson County.
| County | Grade | National percentile |
|---|---|---|
| Boone County | B | 73rd |
| Ford County | B | 73rd |
| Fulton County | B | 71st |
| Iroquois County | B | 71st |
| Jackson County | B | 74th |
FAQ
How often does power go out in Williamson County?
Between 2014 and 2025, Williamson County recorded 365 outage events, averaging 2.4 hours each.
What is Williamson County's reliability grade?
Williamson County has a Reliability Grade of B, in the 72nd national percentile.
What was the worst power outage in Williamson County?
The worst outage on record started January 5, 2025 (Ice Storm), lasting 85 hours and affecting up to 10,894 customers.