Snohomish CountyPower Outage History
What this grade means
Better than average — fewer or shorter outages than most counties. This county's outage history is better than the national median: recorded outages are less frequent and/or shorter in duration than a typical US county experienced over the same 12-year period. It isn't in the top tier nationally, but its track record points to lower-than-average outage risk.
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 hr | 144,105 (22%) | Unnamed event |
| Nov 5, 2022 | <1 hr | 139,466 (21%) | Unnamed event |
| Nov 5, 2022 | <1 hr | 136,408 (21%) | Unnamed event |
| Nov 5, 2022 | 19 hrs | 135,050 (20%) | Unnamed event |
Was There an Outage on a Specific Date?
Pick a date to see whether a power outage was recorded for Snohomish County, Washington that day.
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).
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 |
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 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.