County annual report · FIPS 30057
2020 Madison County, MT Power Outage Report
In 2020, customers in Madison County, MT went without power for an average of 22.4 hours, a total of 139K customer-hours (Montana average 5.6 hours). That ranks 4th worst of 50 Montana counties and 385th of 3,019 nationally.
Compared with MT, the US and 2019
Coverage line is EAGLE-I's share of Montana customers tracked each year.
Biggest outages in Madison County, 2020
The 10 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | November 8, 2020 09:45 | November 9, 2020 02:15 | 16h 30m | 6,110 | 96K |
| 2 | July 3, 2020 21:00 | July 4, 2020 01:00 | 4h | 1,301 | 3,235 |
| 3 | June 6, 2020 02:45 | June 6, 2020 16:45 | 14h | 859 | 3,150 |
| 4 | September 17, 2020 17:45 | September 17, 2020 19:45 | 2h | 724 | 1,448 |
| 5 | May 13, 2020 13:30 | May 13, 2020 19:30 | 6h | 660 | 1,170 |
| 6 | June 2, 2020 05:45 | June 2, 2020 08:15 | 2h 30m | 533 | 936 |
| 7 | August 25, 2020 17:00 | August 26, 2020 21:15 | 1d 4h | 530 | 5,079 |
| 8 | January 23, 2020 01:45 | January 23, 2020 10:00 | 8h 15m | 524 | 2,347 |
| 9 | August 27, 2020 00:15 | August 27, 2020 05:30 | 5h 15m | 508 | 705 |
| 10 | May 18, 2020 21:00 | May 18, 2020 22:15 | 1h 15m | 456 | 570 |
Outage episodes by size in 2020: 27 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 Madison County reported on EIA Form 861 for 2020, 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) | 2020 | 2.8 hrs | 1.13 | 2.0 hrs | 1.02 |
| Vigilante 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 76% of Montana's customers in 2020; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 6,199 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. Madison County has data for 2018–2025.
Cite this report
MassOutage (massoutage.com), Madison County, MT annual power outage report, 2020, 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/2020/montana/madison-county