Montgomery County Power Outage History
2014–2025 · Maryland
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 27, 2022 | 11 hrs | 120,582 (30%) | Unnamed event |
| Mar 2, 2018 | 91 hrs | 108,677 (27%) | Dense Fog |
| Jul 28, 2023 | 85 hrs | 55,999 (14%) | Thunderstorm Wind |
| Oct 8, 2021 | 1 hrs | 42,080 (11%) | Unnamed event |
| Jun 27, 2023 | 3 hrs | 37,874 (10%) | Flood |
Over the 12 years from 2014 to 2025, Montgomery County recorded 3,451 distinct power outage events, averaging 1.9 hours per event.
The single worst outage on record in Montgomery County started November 27, 2022, lasting 11 hours and leaving up to 120,582 customers without power (30% of the county) at its peak.
July has historically been the worst month for outages in Montgomery County, with 437 events recorded during that month across the dataset.
Based on this history, Montgomery County earns a Reliability Grade of B, placing it in the 71st percentile nationally for grid reliability (higher percentile = more reliable).
Sized for Montgomery County's outage profile
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Outage-prep kit
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Similar counties in Maryland
Counties with the closest reliability grade and national percentile to Montgomery County.
| County | Grade | National percentile |
|---|---|---|
| Washington County | B | 72nd |
| Anne Arundel County | B | 69th |
| Somerset County | B | 74th |
| Worcester County | B | 67th |
| Prince George's County | B | 67th |
FAQ
How often does power go out in Montgomery County?
Between 2014 and 2025, Montgomery County recorded 3,451 outage events, averaging 1.9 hours each.
What is Montgomery County's reliability grade?
Montgomery County has a Reliability Grade of B, in the 71st national percentile.
What was the worst power outage in Montgomery County?
The worst outage on record started November 27, 2022, lasting 11 hours and affecting up to 120,582 customers.