Williamson 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 14, 2021 | 93 hrs | 134,418 (34%) | Winter Storm Uri |
| Feb 1, 2023 | 175 hrs | 70,703 (18%) | Winter Storm |
| Feb 11, 2021 | 61 hrs | 28,027 (7%) | Winter Storm Uri |
| Jun 4, 2018 | 22 hrs | 22,402 (6%) | Thunderstorm Wind |
| Mar 21, 2022 | 52 hrs | 22,258 (6%) | Tornado |
Was There an Outage on a Specific Date?
Pick a date to see whether a power outage was recorded for Williamson County, Texas that day.
Over the 12 years from 2014 to 2025, Williamson County recorded 2,241 distinct power outage events, averaging 2.0 hours per event.
The single worst outage on record in Williamson County started February 14, 2021 (Winter Storm Uri), lasting 93 hours and leaving up to 134,418 customers without power (34% of the county) at its peak.
May has historically been the worst month for outages in Williamson County, with 249 events recorded during that month across the dataset.
Based on this history, Williamson County earns a Reliability Grade of C, placing it in the 53rd percentile nationally for grid reliability (higher percentile = more reliable).
Similar counties in Texas
Counties with the closest reliability grade and national percentile to Williamson County.
| County | Grade | National percentile |
|---|---|---|
| Kent County | C | 53rd |
| Shackelford County | C | 53rd |
| Johnson County | C | 53rd |
| Terry County | C | 52nd |
| Ochiltree County | C | 52nd |
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 Williamson County?
Between 2014 and 2025, Williamson County recorded 2,241 outage events, averaging 2.0 hours each.
What is Williamson County's reliability grade?
Williamson County has a Reliability Grade of C, in the 53rd national percentile.
What was the worst power outage in Williamson County?
The worst outage on record started February 14, 2021 (Winter Storm Uri), lasting 93 hours and affecting up to 134,418 customers.