Power outage history
Sioux County Iowa
1.9hours
without power for the average customer in a typical year, 2018–2025
82nd most of 98 in Iowa 71% 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 Sioux's customers who were without power at that day's worst moment.
Year by year
Hours in the dark, per customer
2025 was the worst well-recorded year, at 3.7 hours for the average customer. Hatched years have a thin record and are left out of the averages.
Sioux, 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 |
|---|---|---|---|---|---|---|
| Jul 28, 2025 | Thunderstorms | 4,060 | 24% | 38 h | 17 h | 45k |
| Jun 22, 2024 | Flooding | 2,020 | 12% | 43 h | 22 h | 37k |
| Apr 10, 2019 | Ice storm | 4,636 | 27% | 33 h | 48 min | 35k |
| May 11, 2022 | No storm report | 3,204 | 19% | 15 h | 14 h | 8.8k |
| Jun 15, 2019 | Flooding | 198 | 1% | 46 h | – | 7.9k |
| Apr 2, 2020 | Flooding | 2,459 | 14% | 2.8 h | 2.2 h | 5.2k |
| Sep 28, 2022 | No storm report | 1,830 | 11% | 2.8 h | 1.0 h | 4.7k |
| Nov 28, 2024 | No storm report | 730 | 4% | 4.5 h | – | 2.4k |
| Jul 11, 2024 | No storm report | 3,265 | 19% | 48 min | 48 min | 2.4k |
| Jun 17, 2016 | Thunderstorms | 2,069 | 12% | 3.2 h | 1.5 h | 2.4k |
| Dec 15, 2021 | Windstorm | 791 | 5% | 3.0 h | – | 2.2k |
| Jun 21, 2020 | Thunderstorms | 1,331 | 8% | 6.0 h | 1.8 h | 2.1k |
| May 12, 2022 | Thunderstorms | 890 | 5% | 6.2 h | 5.2 h | 2.1k |
| May 19, 2025 | Windstorm | 512 | 3% | 6.0 h | – | 1.7k |
| Dec 13, 2022 | Winter storm | 616 | 4% | 2.8 h | – | 1.7k |
| Aug 22, 2016 | No storm report | 1,815 | 11% | 1.0 h | 1.0 h | 1.6k |
| Jun 29, 2025 | Thunderstorms | 758 | 4% | 3.2 h | – | 1.5k |
| Aug 18, 2025 | No storm report | 763 | 4% | 2.0 h | – | 1.5k |
| Aug 5, 2018 | Thunderstorms | 761 | 4% | 3.2 h | – | 1.5k |
| Apr 22, 2022 | No storm report | 558 | 3% | 2.5 h | – | 1.4k |
| Apr 12, 2019 | Flooding | 267 | 2% | 11 h | – | 1.3k |
| Dec 25, 2016 | Windstorm | 791 | 5% | 3.0 h | – | 1.1k |
| May 30, 2022 | No storm report | 891 | 5% | 2.2 h | 2.0 h | 1.1k |
| Jan 5, 2022 | Winter storm | 363 | 2% | 2.8 h | – | 998 |
| Sep 4, 2018 | No storm report | 395 | 2% | 2.2 h | – | 889 |
| Jan 3, 2015 | Winter storm | 1,770 | 10% | 48 min | 48 min | 884 |
| Sep 14, 2025 | No storm report | 591 | 3% | 1.5 h | – | 883 |
| May 6, 2024 | No storm report | 497 | 3% | 1.8 h | – | 861 |
| Jun 2, 2024 | No storm report | 362 | 2% | 2.2 h | – | 814 |
| Feb 7, 2019 | No storm report | 435 | 3% | 2.0 h | – | 809 |
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 Sioux from twelve hours before it began to its peak. Matching shows coincidence, not proof of cause.
- Thunderstorms 28%
- Flooding 28%
- No storm on record 22%
- Ice storm 18%
- Windstorm 2.0%
- Winter storm 2.0%
Who keeps the lights on
Utilities serving Sioux
As each utility reports to the Energy Information Administration for its whole Iowa territory, not this county alone. Outage minutes include major storm days.
| Utility | Type | Outage min / yr | Excl. major storms | Outages / yr | Residential ¢/kWh | Customers |
|---|---|---|---|---|---|---|
| MidAmerican Energy Co | Investor Owned | 205 | 82 | 1.19 | 11.2 | 640k |
| Interstate Power and Light Co | Investor Owned | 89 | 74 | 0.82 | 17.8 | 419k |
| Lyon Rural Electric Coop | IA | 173 | 51 | 0.90 | 9.6 | 70k |
| City of Sioux Center | IA | – | – | – | 9.2 | 29k |
| City of Orange City | IA | – | – | – | 9.6 | 24k |
| City of Hawarden | IA | – | – | – | 9.1 | 12k |
| North West Rural Electric Coop | Cooperative | 188 | 115 | 1.11 | 9.4 | 9.5k |
| City of Alton | IA | – | – | – | – | 6.3k |
| WAPA-- Western Area Power Administration | Federal | – | – | – | – | – |
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
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 16,993 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 →