St. Louis County Power Outage History
2014–2025 · Missouri
Bottom 20% least reliable nationally — frequent and/or long outages. How grades are calculated
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Jun 30, 2023 | 147 hrs | 83,685 (59%) | Thunderstorm Wind |
| Aug 12, 2021 | 75 hrs | 69,559 (49%) | Excessive Heat |
| Jul 29, 2023 | 54 hrs | 62,328 (44%) | Excessive Heat |
| Aug 10, 2020 | 66 hrs | 44,212 (31%) | Thunderstorm Wind |
| Jul 10, 2021 | 90 hrs | 40,765 (29%) | Thunderstorm Wind |
Over the 12 years from 2014 to 2025, St. Louis County recorded 2,860 distinct power outage events, averaging 3.1 hours per event.
The single worst outage on record in St. Louis County started June 30, 2023 (Thunderstorm Wind), lasting 147 hours and leaving up to 83,685 customers without power (59% of the county) at its peak.
July has historically been the worst month for outages in St. Louis County, with 381 events recorded during that month across the dataset.
Based on this history, St. Louis County earns a Reliability Grade of F, placing it in the 10th percentile nationally for grid reliability (higher percentile = more reliable).
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Similar counties in Missouri
Counties with the closest reliability grade and national percentile to St. Louis County.
| County | Grade | National percentile |
|---|---|---|
| Reynolds County | F | 20th |
| Iron County | D | 22nd |
| Lawrence County | D | 33rd |
| Bollinger County | D | 36th |
| Holt County | D | 38th |
FAQ
How often does power go out in St. Louis County?
Between 2014 and 2025, St. Louis County recorded 2,860 outage events, averaging 3.1 hours each.
What is St. Louis County's reliability grade?
St. Louis County has a Reliability Grade of F, in the 10th national percentile.
What was the worst power outage in St. Louis County?
The worst outage on record started June 30, 2023 (Thunderstorm Wind), lasting 147 hours and affecting up to 83,685 customers.