Hamilton CountyPower Outage History
2015–2025 · Illinois
Better than average — fewer or shorter outages than most counties.
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Apr 5, 2023 | <1 hr | 2,205 (43%) | Strong Wind |
| Nov 28, 2024 | 1 hrs | 1,668 (32%) | Unnamed event |
| Aug 1, 2024 | 9 hrs | 1,136 (22%) | Hail |
| Feb 7, 2017 | 1 hrs | 918 (18%) | Unnamed event |
| Aug 11, 2020 | 23 hrs | 779 (15%) | Heat |
Over the 11 years from 2015 to 2025, Hamilton County recorded 335 distinct power outage events, averaging 2.0 hours per event.
The single worst outage on record in Hamilton County started April 5, 2023 (Strong Wind), lasting less than 1 hour and leaving up to 2,205 customers without power (43% of the county) at its peak.
June has historically been the worst month for outages in Hamilton County, with 50 events recorded during that month across the dataset.
Based on this history, Hamilton County earns a Reliability Grade of B, placing it in the 77th percentile nationally for grid reliability (higher percentile = more reliable).
Sized for Hamilton 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 Hamilton County.
| County | Grade | National percentile |
|---|---|---|
| Grundy County | B | 77th |
| Moultrie County | B | 77th |
| McDonough County | B | 76th |
| Henry County | B | 78th |
| Union County | B | 76th |
Most reliable counties in Illinois
The top 3 counties in Illinois by reliability grade and percentile.
| County | Grade | National percentile |
|---|---|---|
| Wabash County | A | 97th |
| Massac County | A | 94th |
| Kendall County | A | 93rd |
Least reliable counties in Illinois
The bottom 3 counties in Illinois by reliability grade and percentile.
| County | Grade | National percentile |
|---|---|---|
| Mercer County | F | 11th |
| Stark County | F | 13th |
| Henderson County | F | 19th |
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 Hamilton County?
Between 2015 and 2025, Hamilton County recorded 335 outage events, averaging 2.0 hours each.
What is Hamilton County's reliability grade?
Hamilton County has a Reliability Grade of B, in the 77th national percentile.
What was the worst power outage in Hamilton County?
The worst outage on record started April 5, 2023 (Strong Wind), lasting less than 1 hour and affecting up to 2,205 customers.