Power Out Map
– 0% of Mills out 0 customers out in Iowa

Power outage history

Mills County Iowa

4.8hours

without power for the average customer in a typical year, 2018–2025

33rd most of 98 in Iowa 27% below the national median

Worst outage on record Dec 15, 2021 74% of customers out · 90% back in 31 hours
Hours without power, average customer per year 4.8h / yr State average 5.4 h · national median 6.6 h
Major outages a year 3.4 Peaks over 10% of customers or 50,000 customers
Typical time to restore 90% 3hours Median across major outages, from the peak
Longest single outage 2.4days Dec 15, 2021, over 1% of customers out
Outage hours on storm days 50% Share falling on days with a NOAA storm report here
Worst year 2021 12 hours without power, average customer
Electricity customers 7,270 ORNL customer model · 8 well-covered years

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 Mills's customers who were without power at that day's worst moment.

20152016201720182019202020212022202320242025
0%100% of customers out

Year by year

Hours in the dark, per customer

2021 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.

Mills, hours without power per customer

MillsUS median countyIowa average
0 5 10 15 0.7 ’15 3.8 ’16 8.2 ’17 7.6 ’18 2.2 ’19 3.1 ’20 12 ’21 4.9 ’22 1.5 ’23 4.0 ’24 2.5 ’25 US 6.6 IA 5.4

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
Dec 15, 2021 Tornadoes 5,353 74% 2.4 d 31 h 67k
Jun 16, 2017 Tornadoes 3,779 52% 38 h 22 h 47k
Jan 21, 2018 No storm report 6,702 92% 6.2 h 6.0 h 27k
Jun 15, 2022 Thunderstorms 2,540 35% 12 h 10 h 26k
Feb 2, 2016 No storm report 2,198 30% 9.5 h 5.2 h 11k
Mar 14, 2021 No storm report 2,054 28% 3.0 h 3.2 h 6.0k
Mar 9, 2020 No storm report 2,065 28% 3.5 h 3.2 h 5.0k
Jun 12, 2018 No storm report 418 6% 13 h 11 h 4.8k
Jul 10, 2021 No storm report 539 7% 13 h 11 h 4.2k
Nov 25, 2025 Windstorm 941 13% 5.0 h 2.0 h 4.1k
Jun 24, 2024 Flooding 185 3% 28 h – 4.0k
May 23, 2019 No storm report 1,022 14% 4.5 h 1.5 h 3.9k

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.

0% 25% 50% 75% 100% peak+24h+48h+72h+96h half back by +6h 90% by +6h

When it happens

The outage clock

Customer-hours out by month (rings, January innermost) and local hour, 2018–2025.

00061218 Jan inside

What was happening

Weather behind the outages

Each outage is matched to NOAA storm reports for Mills from twelve hours before it began to its peak. Matching shows coincidence, not proof of cause.

  • No storm on record 50%
  • Tornadoes 28%
  • Thunderstorms 14%
  • Flooding 3.0%
  • Winter storm 2.6%
  • Windstorm 1.7%

Who keeps the lights on

Utilities serving Mills

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
Southwest Iowa Rural Elec Coop IA 122 122 1.69 12.5 75k

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

Across Iowa

Where it is darkest

Hours / yr64+

All Iowa 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 7,270 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 →