Snohomish County Power Outage History
2019–2025 · Washington
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 |
|---|---|---|---|
| Nov 4, 2022 | 12 hrs | 166,046 (25%) | Unnamed event |
| Nov 5, 2022 | 1 hrs | 144,105 (22%) | Unnamed event |
| Nov 5, 2022 | 1 hrs | 139,466 (21%) | Unnamed event |
| Nov 5, 2022 | 1 hrs | 136,408 (21%) | Unnamed event |
| Nov 5, 2022 | 19 hrs | 135,050 (20%) | Unnamed event |
Over the 7 years from 2019 to 2025, Snohomish County recorded 1,450 distinct power outage events, averaging 3.2 hours per event.
The single worst outage on record in Snohomish County started November 4, 2022, lasting 12 hours and leaving up to 166,046 customers without power (25% of the county) at its peak.
August has historically been the worst month for outages in Snohomish County, with 148 events recorded during that month across the dataset.
Based on this history, Snohomish County earns a Reliability Grade of B, placing it in the 70th percentile nationally for grid reliability (higher percentile = more reliable).
Sized for Snohomish County's outage profile
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Similar counties in Washington
Counties with the closest reliability grade and national percentile to Snohomish County.
| County | Grade | National percentile |
|---|---|---|
| Spokane County | B | 69th |
| Walla Walla County | B | 76th |
| Columbia County | B | 63rd |
| Whitman County | B | 78th |
| Yakima County | B | 80th |
FAQ
How often does power go out in Snohomish County?
Between 2019 and 2025, Snohomish County recorded 1,450 outage events, averaging 3.2 hours each.
What is Snohomish County's reliability grade?
Snohomish County has a Reliability Grade of B, in the 70th national percentile.
What was the worst power outage in Snohomish County?
The worst outage on record started November 4, 2022, lasting 12 hours and affecting up to 166,046 customers.