PowerOutageHistory
C

Jefferson County Power Outage History

20142025 · Colorado

Average — typical outage frequency and duration nationally. How grades are calculated

Total events
2,898
Avg duration
2.2 hrs
Longest outage
142 hrs
National percentile
45th

Outages by year

Outages by month (seasonality)

Worst outage events on record

DateDurationCustomers affectedCause
Feb 15, 20191 hrs156,331 (56%)High Wind
Apr 6, 202486 hrs73,150 (26%)High Wind
May 21, 202268 hrs57,450 (21%)Winter Storm
Dec 17, 2025142 hrs51,319 (18%)High Wind
Mar 25, 20245 hrs42,214 (15%)Winter Weather

Over the 12 years from 2014 to 2025, Jefferson County recorded 2,898 distinct power outage events, averaging 2.2 hours per event.

The single worst outage on record in Jefferson County started February 15, 2019 (High Wind), lasting 1 hours and leaving up to 156,331 customers without power (56% of the county) at its peak.

July has historically been the worst month for outages in Jefferson County, with 397 events recorded during that month across the dataset.

Based on this history, Jefferson County earns a Reliability Grade of C, placing it in the 45th percentile nationally for grid reliability (higher percentile = more reliable).

Sized for Jefferson County's outage profile

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Outage-prep kit

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Similar counties in Colorado

Counties with the closest reliability grade and national percentile to Jefferson County.

CountyGradeNational percentile
Archuleta CountyC44th
Boulder CountyC48th
Costilla CountyC50th
Teller CountyC52nd
Crowley CountyC52nd

FAQ

How often does power go out in Jefferson County?

Between 2014 and 2025, Jefferson County recorded 2,898 outage events, averaging 2.2 hours each.

What is Jefferson County's reliability grade?

Jefferson County has a Reliability Grade of C, in the 45th national percentile.

What was the worst power outage in Jefferson County?

The worst outage on record started February 15, 2019 (High Wind), lasting 1 hours and affecting up to 156,331 customers.

Data: ORNL EAGLE-I Recorded Electricity Outages (2014–2025), CC BY 4.0. Storm names: NOAA Storm Events Database. Last data refresh: 2025. See methodology.