Power outage history
Dallas County Iowa
2.5hours
without power for the average customer in a typical year, 2018–2025
65th most of 98 in Iowa 61% 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 Dallas's customers who were without power at that day's worst moment.
Year by year
Hours in the dark, per customer
2020 was the worst well-recorded year, at 12 hours for the average customer. Hatched years have a thin record and are left out of the averages.
Dallas, 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 |
|---|---|---|---|---|---|---|
| Aug 10, 2020 | Thunderstorms | 19,149 | 33% | 5.0 d | 3.2 d | 636k |
| Mar 5, 2025 | Winter storm | 5,911 | 10% | 20 h | 15 h | 61k |
| Aug 15, 2020 | No storm report | 2,198 | 4% | 41 h | – | 29k |
| Jul 23, 2022 | No storm report | 6,523 | 11% | 5.8 h | 4.0 h | 23k |
| Jul 28, 2025 | No storm report | 2,279 | 4% | 10 h | – | 13k |
| Aug 17, 2015 | No storm report | 7,066 | 12% | 2.5 h | 2.0 h | 11k |
| Dec 5, 2021 | No storm report | 4,609 | 8% | 2.2 h | 1.5 h | 10k |
| May 24, 2024 | Thunderstorms | 4,226 | 7% | 3.0 h | 3.2 h | 9.4k |
| Aug 11, 2016 | Thunderstorms | 1,738 | 3% | 6.5 h | – | 9.1k |
| May 17, 2017 | Thunderstorms | 4,436 | 8% | 3.2 h | 3.2 h | 9.1k |
| Jul 30, 2024 | No storm report | 3,149 | 5% | 4.0 h | 4.0 h | 9.0k |
| Dec 16, 2021 | Windstorm | 2,148 | 4% | 4.2 h | – | 7.8k |
| Jun 25, 2023 | No storm report | 3,388 | 6% | 4.2 h | 4.2 h | 6.7k |
| Aug 26, 2020 | No storm report | 5,010 | 9% | 1.5 h | 1.2 h | 6.4k |
| Apr 3, 2024 | No storm report | 3,023 | 5% | 3.0 h | 1.8 h | 5.8k |
| Sep 23, 2025 | No storm report | 6,037 | 10% | 1.0 h | 4.5 h | 5.5k |
| Apr 13, 2018 | Thunderstorms | 4,206 | 7% | 2.2 h | 2.0 h | 5.3k |
| Sep 30, 2021 | No storm report | 1,644 | 3% | 6.0 h | – | 5.3k |
| Dec 15, 2021 | Thunderstorms | 2,061 | 4% | 3.2 h | – | 5.1k |
| Jul 30, 2025 | No storm report | 1,705 | 3% | 3.0 h | – | 4.9k |
| Apr 22, 2022 | Flooding | 746 | 1% | 6.5 h | – | 4.6k |
| Jul 19, 2016 | Thunderstorms | 2,805 | 5% | 5.0 h | – | 4.3k |
| Sep 22, 2025 | No storm report | 2,379 | 4% | 1.8 h | – | 4.2k |
| Jul 30, 2024 | No storm report | 1,567 | 3% | 2.2 h | – | 3.5k |
| Oct 22, 2016 | No storm report | 1,965 | 3% | 1.8 h | – | 3.4k |
| Jan 15, 2022 | Winter storm | 2,094 | 4% | 3.0 h | – | 3.4k |
| Jun 13, 2022 | No storm report | 4,464 | 8% | 48 min | 1.0 h | 3.3k |
| Jun 7, 2025 | No storm report | 1,647 | 3% | 3.5 h | – | 3.3k |
| Aug 8, 2023 | No storm report | 3,069 | 5% | 1.2 h | 1.2 h | 3.3k |
| Nov 19, 2023 | No storm report | 2,171 | 4% | 1.5 h | – | 3.1k |
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 Dallas from twelve hours before it began to its peak. Matching shows coincidence, not proof of cause.
- Thunderstorms 69%
- No storm on record 23%
- Winter storm 7.0%
- Windstorm 0.8%
- Flooding 0.8%
Who keeps the lights on
Utilities serving Dallas
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 |
| Guthrie County Rural E C A | IA | – | – | – | 10.4 | 72k |
| Waverly Municipal Elec Utility | IA | 7 | 7 | 0.14 | 14.1 | 41k |
| Midland Power Coop | Cooperative | 488 | 91 | 1.79 | 13.7 | 12k |
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.
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 58,451 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 →