– 0% of Boulder out 0 customers out in Colorado

Power outage history

Boulder County Colorado

5.3hours

without power for the average customer in a typical year, 2018–2025

11th most of 39 in Colorado 20% below the national median

Worst outage on record Dec 17, 2025 36% of customers out · 90% back in 26 hours
Hours without power, average customer per year 5.3h / yr State average 3.0 h · national median 6.6 h
Major outages a year 0.6 Peaks over 10% of customers or 50,000 customers
Typical time to restore 90% 14hours Median across major outages, from the peak
Longest single outage 4.4days Dec 17, 2025, over 1% of customers out
Outage hours on storm days 91% Share falling on days with a NOAA storm report here
Worst year 2025 17 hours without power, average customer
Electricity customers 166,613 ORNL customer model · 8 well-covered years

Every day since 2015

Eleven years, one night at a time

Each cell is a day. The brighter it is, the larger the share of Boulder's customers who were without power at that day's worst moment.

20152016201720182019202020212022202320242025
0%100% of customers out

Year by year

Hours in the dark, per customer

2025 was the worst well-recorded year, at 17 hours for the average customer. Hatched years have a thin record and are left out of the averages.

Boulder, hours without power per customer

BoulderUS median countyColorado average
0 5 10 15 20 1.0 ’15 2.2 ’16 1.8 ’17 1.5 ’18 2.4 ’19 2.4 ’20 2.8 ’21 3.2 ’22 1.4 ’23 12 ’24 17 ’25 US 6.6 CO 3.0

The record

The biggest outages since 2015

Ranked by customer-hours lost: customers out multiplied by how long they stayed out. Times are local.

Began Storm Peak out Share Lasted 90% restored Customer-hours
Dec 17, 2025 Windstorm 60,021 36% 4.4 d 26 h 2.3M
Apr 6, 2024 Windstorm 40,368 24% 2.3 d 33 h 1.4M
Dec 31, 2021 Winter storm 28,183 17% 46 h 26 h 244k
Mar 23, 2016 Winter storm 28,537 17% 23 h 1.8 h 186k
Dec 30, 2021 Winter storm 23,120 14% 8.8 h 2.5 h 125k
Dec 15, 2021 Winter storm 11,600 7% 14 h 16 h 104k
May 18, 2017 Winter storm 10,234 6% 25 h 25 h 85k
May 5, 2019 No storm report 5,992 4% 15 h 14 h 63k
Sep 8, 2020 Winter storm 16,554 10% 20 h 8.8 h 62k
Mar 14, 2024 Winter storm 20,891 13% 19 h 12 min 61k
May 6, 2024 Windstorm 3,747 2% 21 h – 54k
May 21, 2022 Winter storm 3,759 2% 14 h – 34k

After the peak

How fast the lights come back

Each line is one major outage, from its peak. The amber line is the typical path.

0% 25% 50% 75% 100% peak+24h+48h+72h+96h half back by +2h 90% by +16h

When it happens

The outage clock

Customer-hours out by month (rings, January innermost) and local hour, 2018–2025.

00061218 Jan inside

What was happening

Weather behind the outages

Each outage is matched to NOAA storm reports for Boulder from twelve hours before it began to its peak. Matching shows coincidence, not proof of cause.

  • Windstorm 75%
  • Winter storm 14%
  • No storm on record 9.5%
  • Wildfire 1.0%

Who keeps the lights on

Utilities serving Boulder

As each utility reports to the Energy Information Administration for its whole Colorado territory, not this county alone. Outage minutes include major storm days.

Utility Type Outage min / yr Excl. major storms Outages / yr Residential ¢/kWh Customers
Public Service Co of Colorado Investor Owned 360 149 1.58 15.9 1.4M
United Power, Inc Cooperative 303 90 1.18 16.5 103k
Town of Estes Park CO – – – 14.2 60k
Poudre Valley REA, Inc Cooperative 151 49 1.03 12.5 51k
City of Longmont Municipal 40 40 0.56 13.1 41k
Town of Lyons CO – – – – 7.3k
WAPA-- Western Area Power Administration Federal – – – – –

EIA Form 861, latest year each utility reported. Outage minutes are SAIDI, the yearly minutes the average customer goes without power; outages a year are SAIFI.

Next door

Neighbouring counties

Across Colorado

Where it is darkest

Hours / yr64+

All Colorado counties →

About these numbers

Notes

Outages come from the EAGLE-I record of utility outage maps collected every 15 minutes by Oak Ridge National Laboratory. Hours without power are customer-hours divided by the county's 166,613 electricity customers. Averages use well-covered years from 2018. Outages shorter than 15 minutes, and utilities that publish no outage map, are not in the record, so these figures understate the total. How every number is made →