County annual report · FIPS 30087
2018 Rosebud County, MT Power Outage Report
In 2018, customers in Rosebud County, MT went without power for an average of 2.0 hours, a total of 9,195 customer-hours (Montana average 1.9 hours). That ranks 8th worst of 20 Montana counties and 1880th of 2,798 nationally.
Compared with MT, the US and 2017
Coverage line is EAGLE-I's share of Montana customers tracked each year.
Biggest outages in Rosebud County, 2018
The 10 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | August 30, 2018 06:15 | August 30, 2018 12:30 | 6h 15m | 1,143 | 7,054 |
| 2 | May 6, 2018 04:45 | May 6, 2018 06:00 | 1h 15m | 1,138 | 1,423 |
| 3 | May 11, 2018 05:00 | May 11, 2018 05:15 | 15m | 650 | 163 |
| 4 | June 8, 2018 00:30 | June 8, 2018 05:45 | 5h 15m | 271 | 404 |
| 5 | January 3, 2018 19:45 | January 3, 2018 20:00 | 15m | 124 | 31 |
| 6 | July 10, 2018 20:00 | July 10, 2018 20:15 | 15m | 68 | 17 |
| 7 | February 19, 2018 06:00 | February 19, 2018 06:15 | 15m | 37 | 9 |
| 8 | January 31, 2018 08:00 | January 31, 2018 08:15 | 15m | 33 | 8 |
| 9 | February 1, 2018 04:00 | February 1, 2018 04:15 | 15m | 31 | 8 |
| 10 | April 11, 2018 07:30 | April 11, 2018 08:30 | 1h | 29 | 29 |
Outage episodes by size in 2018: 5 reached 100+ customers, 2 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 Rosebud County reported on EIA Form 861 for 2018, 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) | 2018 | 1.7 hrs | 1.08 | 1.7 hrs | 1.08 |
| Mid-Yellowstone Elec Coop, Inc | 2018 | 4.5 hrs | 3.82 | 4.5 hrs | 3.82 |
| WAPA-- Western Area Power Administration | - | - | - | - | - |
| Montana-Dakota Utilities Co | - | - | - | - | - |
| McCone Electric Coop Inc | - | - | - | - | - |
| Tongue River Electric Coop Inc | - | - | - | - | - |
About this data
- Outage figures come from DOE/ORNL EAGLE-I, which records customers out by county every 15 minutes. EAGLE-I tracked about 16% of Montana's customers in 2018; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 4,647 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. Rosebud County has data for 2017–2025.
Cite this report
MassOutage (massoutage.com), Rosebud County, MT annual power outage report, 2018, 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/2018/montana/rosebud-county