County annual report · FIPS 55139
2025 Winnebago County, WI Power Outage Report
In 2025, customers in Winnebago County, WI went without power for an average of 1.2 hours, a total of 88K customer-hours (Wisconsin average 3.9 hours). That ranks 59th worst of 72 Wisconsin counties and 2708th of 3,000 nationally.
Compared with WI, the US and 2024
Coverage line is EAGLE-I's share of Wisconsin customers tracked each year.
Biggest outages in Winnebago County, 2025
The 10 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | June 12, 2025 14:00 | June 12, 2025 15:45 | 1h 45m | 4,706 | 4,708 |
| 2 | March 4, 2025 14:30 | March 4, 2025 15:45 | 1h 15m | 4,704 | 2,406 |
| 3 | March 27, 2025 01:30 | March 27, 2025 05:30 | 4h | 3,910 | 3,904 |
| 4 | June 23, 2025 19:30 | June 24, 2025 23:00 | 1d 3h | 3,533 | 10K |
| 5 | June 21, 2025 20:00 | June 21, 2025 21:45 | 1h 45m | 3,307 | 1,063 |
| 6 | May 16, 2025 18:30 | May 17, 2025 22:30 | 1d 4h | 2,582 | 14K |
| 7 | August 9, 2025 07:00 | August 10, 2025 20:15 | 1d 13h | 2,478 | 7,149 |
| 8 | December 28, 2025 09:30 | December 28, 2025 19:30 | 10h | 1,964 | 5,482 |
| 9 | April 14, 2025 16:45 | April 14, 2025 18:45 | 2h | 1,809 | 1,814 |
| 10 | March 20, 2025 00:15 | March 20, 2025 15:15 | 15h | 1,638 | 2,513 |
Outage episodes by size in 2025: 36 reached 100+ customers, 13 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 Winnebago County reported on EIA Form 861 for 2025, 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 |
|---|---|---|---|---|---|
| Wisconsin Electric Power Co | 2024 | 4.9 hrs | 1.04 | 1.8 hrs | 0.74 |
| Wisconsin Public Service Corp | 2024 | 7.8 hrs | 1.22 | 1.6 hrs | 0.77 |
| Alliant Energy (Interstate Power & Light) | - | - | - | - | - |
| Wisconsin Power & Light Co | - | - | - | - | - |
| City of Menasha - (WI) | - | - | - | - | - |
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 Wisconsin's customers in 2025; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 74,573 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. Winnebago County has data for 2015–2025.
Cite this report
MassOutage (massoutage.com), Winnebago County, WI annual power outage report, 2025, 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/2025/wisconsin/winnebago-county