County annual report · FIPS 30063
2023 Missoula County, MT Power Outage Report
In 2023, customers in Missoula County, MT went without power for an average of 2.3 hours, a total of 131K customer-hours (Montana average 1.8 hours). That ranks 20th worst of 50 Montana counties and 2192nd of 2,977 nationally.
Compared with MT, the US and 2022
Coverage line is EAGLE-I's share of Montana customers tracked each year.
Biggest outages in Missoula County, 2023
The 10 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | May 9, 2023 14:00 | May 9, 2023 15:45 | 1h 45m | 7,478 | 8,652 |
| 2 | December 20, 2023 23:45 | December 21, 2023 01:00 | 1h 15m | 6,344 | 7,137 |
| 3 | March 21, 2023 16:45 | March 21, 2023 18:30 | 1h 45m | 5,397 | 9,445 |
| 4 | December 20, 2023 07:15 | December 20, 2023 08:30 | 1h 15m | 3,746 | 4,682 |
| 5 | November 25, 2023 16:30 | November 25, 2023 21:30 | 5h | 3,172 | 11K |
| 6 | November 7, 2023 20:45 | November 7, 2023 22:15 | 1h 30m | 2,243 | 2,243 |
| 7 | January 27, 2023 19:30 | January 27, 2023 22:45 | 3h 15m | 2,035 | 2,087 |
| 8 | October 25, 2023 09:00 | October 25, 2023 17:45 | 8h 45m | 2,013 | 3,716 |
| 9 | January 17, 2023 07:15 | January 17, 2023 09:15 | 2h | 1,915 | 2,873 |
| 10 | February 14, 2023 20:30 | February 14, 2023 22:00 | 1h 30m | 1,839 | 2,757 |
Outage episodes by size in 2023: 61 reached 100+ customers, 18 reached 1,000+ customers, 0 reached 10,000+ customers.
Utility reliability filed with the EIA
SAIDI (average outage time per customer) and SAIFI (average interruptions per customer) that utilities serving Missoula County reported on EIA Form 861 for 2023, or their most recent earlier filing. Utility-wide figures, not county-specific.
| Utility | EIA year | SAIDI | SAIFI | SAIDI excl. major events | SAIFI excl. major events |
|---|---|---|---|---|---|
| NorthWestern Energy LLC - (MT) | 2023 | 1.7 hrs | 0.93 | 1.7 hrs | 0.93 |
| Missoula Electric Coop, Inc | 2023 | 2.8 hrs | 1.19 | 2.8 hrs | 1.19 |
| Ravalli County Elec Coop, Inc | 2018 | 4.2 hrs | 1.53 | 2.5 hrs | 1.41 |
| Bonneville Power Administration | - | - | - | - | - |
| NorthWestern Energy | - | - | - | - | - |
| USBIA-Mission Valley Power | - | - | - | - | - |
About this data
- Outage figures come from DOE/ORNL EAGLE-I, which records customers out by county every 15 minutes. EAGLE-I tracked about n/a of Montana's customers in 2023; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 57,348 customers (ORNL modeled county customer count), including major storm days. It is comparable across counties but is not the SAIDI a utility files.
- An outage event is a continuous stretch with customers out; counts at 100, 1,000 and 10,000+ use its peak.
- Years loaded: 2015–2025. Missoula County has data for 2019–2025.
Cite this report
MassOutage (massoutage.com), Missoula County, MT annual power outage report, 2023, data as of Oct 3, 2026 02:41 UTC, sources: DOE EAGLE-I (https://eagle-i.doe.gov/); EAGLE-I modeled customer counts (MCC) (https://figshare.com/); EIA Form 861 (utility reliability) (https://www.eia.gov/electricity/data/eia861/). https://massoutage.com/reports/2023/montana/missoula-county