Power outage history
Musselshell County Montana
5.6hours
without power for the average customer in a typical year, 2018–2025
19th most of 35 in Montana 14% below the national median
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 Musselshell's customers who were without power at that day's worst moment.
Year by year
Hours in the dark, per customer
2023 was the worst well-recorded year, at 11 hours for the average customer. Hatched years have a thin record and are left out of the averages.
Musselshell, hours without power per customer
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 |
|---|---|---|---|---|---|---|
| Apr 19, 2023 | No storm report | 466 | 20% | 4.5 d | 39 h | 17k |
| Nov 13, 2024 | No storm report | 2,012 | 85% | 4.5 h | 4.5 h | 9.1k |
| Aug 17, 2025 | No storm report | 454 | 19% | 12 h | 13 h | 4.5k |
| Nov 16, 2020 | No storm report | 472 | 20% | 7.8 h | 7.5 h | 3.3k |
| Jul 28, 2025 | Thunderstorms | 528 | 22% | 9.8 h | 48 min | 3.1k |
| May 26, 2023 | No storm report | 388 | 16% | 7.5 h | 6.8 h | 2.8k |
| Sep 4, 2025 | No storm report | 541 | 23% | 5.2 h | 2.0 h | 2.1k |
| Jul 23, 2022 | No storm report | 448 | 19% | 4.5 h | 4.5 h | 1.9k |
| Nov 29, 2025 | No storm report | 574 | 24% | 5.5 h | 3.0 h | 1.9k |
| Jul 14, 2025 | No storm report | 486 | 21% | 5.0 h | 7.5 h | 1.7k |
| Apr 18, 2024 | No storm report | 164 | 7% | 9.5 h | 9.5 h | 1.5k |
| Aug 18, 2025 | No storm report | 541 | 23% | 2.8 h | 2.8 h | 1.5k |
| Jun 22, 2024 | No storm report | 87 | 4% | 24 h | – | 1.4k |
| May 20, 2020 | No storm report | 401 | 17% | 3.2 h | 3.2 h | 1.3k |
| Jan 11, 2022 | No storm report | 356 | 15% | 3.2 h | 3.2 h | 1.2k |
| Jun 24, 2023 | No storm report | 39 | 2% | 34 h | – | 924 |
| Jun 7, 2020 | No storm report | 182 | 8% | 9.2 h | 6.0 h | 887 |
| Mar 5, 2020 | No storm report | 102 | 4% | 13 h | – | 744 |
| Jan 26, 2023 | No storm report | 102 | 4% | 7.2 h | – | 740 |
| Jun 10, 2023 | No storm report | 36 | 2% | 28 h | – | 686 |
| Nov 13, 2021 | Windstorm | 105 | 4% | 8.2 h | – | 677 |
| Aug 19, 2024 | No storm report | 300 | 13% | 2.2 h | 3.5 h | 675 |
| Nov 9, 2022 | No storm report | 507 | 21% | 1.2 h | 1.2 h | 634 |
| Oct 25, 2022 | No storm report | 507 | 21% | 1.2 h | 1.2 h | 634 |
| Jan 20, 2022 | No storm report | 81 | 3% | 7.5 h | – | 608 |
| Jan 14, 2021 | Windstorm | 58 | 2% | 17 h | – | 564 |
| Jan 5, 2022 | No storm report | 356 | 15% | 2.2 h | 1.5 h | 555 |
| May 7, 2024 | Windstorm | 58 | 2% | 9.5 h | – | 508 |
| Oct 29, 2025 | No storm report | 87 | 4% | 5.5 h | – | 476 |
| Jul 18, 2024 | No storm report | 132 | 6% | 5.8 h | 5.2 h | 461 |
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.
When it happens
The outage clock
Customer-hours out by month (rings, January innermost) and local hour, 2018–2025.
What was happening
Weather behind the outages
Each outage is matched to NOAA storm reports for Musselshell from twelve hours before it began to its peak. Matching shows coincidence, not proof of cause.
- No storm on record 92%
- Thunderstorms 4.3%
- Windstorm 3.3%
Who keeps the lights on
Utilities serving Musselshell
As each utility reports to the Energy Information Administration for its whole Montana territory, not this county alone. Outage minutes include major storm days.
| Utility | Type | Outage min / yr | Excl. major storms | Outages / yr | Residential ¢/kWh | Customers |
|---|---|---|---|---|---|---|
| NorthWestern Energy LLC | Investor Owned | 125 | 117 | 1.10 | 14.4 | 334k |
| Yellowstone Valley Elec Co-op | Cooperative | – | – | – | 14.2 | 21k |
| Fergus Electric Coop, Inc | Cooperative | 480 | 284 | 3.03 | 15.9 | 6.9k |
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
- Golden Valley 13 h
- Musselshell (this county) 5.6 h
- Fergus 4.1 h
- Rosebud 3.1 h
- Yellowstone 2.4 h
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 2,362 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 →