Power Out Map
– 0% of Big Horn out 0 customers out in Wyoming

Power outage history

Big Horn County Wyoming

3.0hours

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

9th most of 20 in Wyoming 55% below the national median

Worst outage on record Jul 26, 2018 19% of customers out · 90% back in 13 hours
Hours without power, average customer per year 3.0h / yr State average 2.4 h · national median 6.6 h
Major outages a year 3.8 Peaks over 10% of customers or 50,000 customers
Typical time to restore 90% 2hours Median across major outages, from the peak
Longest single outage 16hours Jul 26, 2018, over 1% of customers out
Outage hours on storm days 22% Share falling on days with a NOAA storm report here
Worst year 2018 4.3 hours without power, average customer
Electricity customers 3,930 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 Big Horn'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

2018 was the worst well-recorded year, at 4.3 hours for the average customer. Hatched years have a thin record and are left out of the averages.

Big Horn, hours without power per customer

Big HornUS median countyWyoming average
0 2 4 6 8 ’17 4.3 ’18 1.4 ’19 2.8 ’20 3.6 ’21 1.8 ’22 3.0 ’23 2.5 ’24 4.1 ’25 US 6.6 WY 2.4

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
Jul 26, 2018 Thunderstorms 755 19% 16 h 13 h 6.1k
Aug 1, 2020 No storm report 2,279 58% 2.8 h 2.0 h 5.5k
Jun 13, 2025 No storm report 1,278 33% 3.5 h 3.2 h 4.2k
May 6, 2021 No storm report 1,271 32% 3.5 h 2.5 h 3.8k
Jun 12, 2025 No storm report 1,596 41% 4.5 h 4.5 h 3.7k
Mar 24, 2023 No storm report 1,282 33% 2.8 h 2.5 h 3.3k
Apr 8, 2021 Windstorm 1,771 45% 2.0 h 1.5 h 3.2k
Nov 19, 2025 No storm report 1,675 43% 3.2 h 48 min 3.1k
Oct 1, 2018 No storm report 1,423 36% 2.5 h 1.8 h 2.5k
Apr 15, 2024 No storm report 1,656 42% 1.5 h 1.5 h 2.5k
Jun 12, 2023 No storm report 1,282 33% 2.0 h 8.5 h 2.4k
May 27, 2018 Thunderstorms 1,319 34% 3.5 h 1.2 h 2.4k

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 +4h

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 Big Horn from twelve hours before it began to its peak. Matching shows coincidence, not proof of cause.

  • No storm on record 78%
  • Thunderstorms 14%
  • Windstorm 5.5%
  • Winter storm 2.1%

Who keeps the lights on

Utilities serving Big Horn

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

Utility Type Outage min / yr Excl. major storms Outages / yr Residential ¢/kWh Customers
PacifiCorp Investor Owned 195 91 1.37 15.1 119k
Big Horn Rural Electric Co WY 208 – 1.29 14.9 31k
Garland Light & Power Company WY – – – 15.3 22k
High Plains Power Inc Cooperative 320 263 – 14.2 13k
Town of Basin WY – – – – 3.7k
City of Deaver WY – – – – 675
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 Wyoming

Where it is darkest

Hours / yr64+

All Wyoming 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 3,930 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 →