Power outage history
Montgomery County Iowa
2.5hours
without power for the average customer in a typical year, 2018–2025
67th most of 98 in Iowa 63% 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 Montgomery's customers who were without power at that day's worst moment.
Year by year
Hours in the dark, per customer
2024 was the worst well-recorded year, at 4.7 hours for the average customer. Hatched years have a thin record and are left out of the averages.
Montgomery, 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 |
|---|---|---|---|---|---|---|
| May 21, 2024 | Tornadoes | 732 | 13% | 47 h | 44 h | 17k |
| Dec 15, 2021 | Windstorm | 715 | 12% | 20 h | 18 h | 5.4k |
| Jul 6, 2016 | No storm report | 2,469 | 43% | 5.0 h | 2.5 h | 5.1k |
| Oct 11, 2020 | Thunderstorms | 778 | 14% | 14 h | 9.5 h | 4.7k |
| Dec 1, 2021 | No storm report | 4,346 | 76% | 1.0 h | 30 min | 4.2k |
| Sep 26, 2020 | No storm report | 86 | 2% | 40 h | – | 3.3k |
| Jun 11, 2025 | No storm report | 473 | 8% | 9.2 h | 9.2 h | 3.2k |
| Sep 1, 2018 | Thunderstorms | 1,388 | 24% | 5.5 h | 2.2 h | 3.0k |
| Jan 9, 2024 | Winter storm | 470 | 8% | 11 h | 48 min | 2.9k |
| Jun 11, 2018 | Thunderstorms | 560 | 10% | 12 h | 11 h | 2.4k |
| Jun 8, 2023 | No storm report | 1,178 | 21% | 1.8 h | 11 h | 2.1k |
| Jul 10, 2021 | No storm report | 195 | 3% | 12 h | – | 1.7k |
| Jun 16, 2017 | Thunderstorms | 438 | 8% | 6.0 h | 5.5 h | 1.6k |
| Jul 17, 2022 | No storm report | 308 | 5% | 6.8 h | 6.8 h | 1.6k |
| Apr 14, 2023 | Thunderstorms | 269 | 5% | 5.5 h | – | 1.4k |
| Jun 2, 2018 | No storm report | 280 | 5% | 6.8 h | – | 1.2k |
| Mar 10, 2022 | No storm report | 299 | 5% | 8.8 h | 4.2 h | 1.1k |
| Jul 19, 2016 | No storm report | 457 | 8% | 4.0 h | 2.5 h | 1.1k |
| Nov 26, 2015 | No storm report | 164 | 3% | 9.0 h | – | 1.0k |
| Nov 29, 2022 | No storm report | 404 | 7% | 5.8 h | 4.0 h | 1.0k |
| Jun 24, 2023 | No storm report | 250 | 4% | 4.0 h | – | 998 |
| Mar 5, 2022 | Tornadoes | 111 | 2% | 8.8 h | – | 964 |
| Mar 4, 2025 | Winter storm | 290 | 5% | 5.2 h | 5.0 h | 960 |
| Oct 3, 2018 | No storm report | 258 | 5% | 5.5 h | – | 896 |
| Jun 15, 2024 | No storm report | 1,176 | 21% | 48 min | 48 min | 882 |
| Jul 1, 2020 | No storm report | 291 | 5% | 5.0 h | 12 min | 880 |
| Jul 7, 2025 | Thunderstorms | 276 | 5% | 3.8 h | – | 866 |
| Mar 16, 2018 | No storm report | 549 | 10% | 1.5 h | 1.5 h | 824 |
| Jun 26, 2024 | Heat | 681 | 12% | 1.2 h | 1.2 h | 822 |
| Jul 30, 2021 | No storm report | 219 | 4% | 4.5 h | – | 735 |
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 Montgomery from twelve hours before it began to its peak. Matching shows coincidence, not proof of cause.
- No storm on record 48%
- Tornadoes 21%
- Thunderstorms 17%
- Windstorm 6.3%
- Winter storm 5.3%
- Heat 1.9%
- Tropical storm 0.6%
Who keeps the lights on
Utilities serving Montgomery
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 |
| Southwest Iowa Rural Elec Coop | IA | 122 | 122 | 1.69 | 12.5 | 75k |
| City of Villisca | IA | – | – | – | – | 6.9k |
| City of Stanton | IA | – | – | – | – | 5.6k |
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 5,724 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 →