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

Power outage history

Jefferson County Iowa

4.0hours

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

42nd most of 98 in Iowa 38% below the national median

Worst outage on record Mar 31, 2023 22% of customers out · 90% back in 16 hours
Hours without power, average customer per year 4.0h / yr State average 5.4 h · national median 6.6 h
Major outages a year 5.4 Peaks over 10% of customers or 50,000 customers
Typical time to restore 90% 1hours Median across major outages, from the peak
Longest single outage 21hours Mar 31, 2023, over 1% of customers out
Outage hours on storm days 22% Share falling on days with a NOAA storm report here
Worst year 2020 6.6 hours without power, average customer
Electricity customers 6,879 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 Jefferson'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

2020 was the worst well-recorded year, at 6.6 hours for the average customer. Hatched years have a thin record and are left out of the averages.

Jefferson, hours without power per customer

JeffersonUS median countyIowa average
0 2 4 6 8 3.1 ’15 3.9 ’16 2.5 ’17 6.1 ’18 2.1 ’19 6.6 ’20 2.7 ’21 1.6 ’22 5.3 ’23 5.5 ’24 2.6 ’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
Mar 31, 2023 No storm report 1,495 22% 21 h 16 h 20k
Jan 23, 2016 No storm report 4,479 65% 4.8 h 10 h 16k
Jul 15, 2020 No storm report 4,622 67% 3.0 h 3.0 h 14k
Jun 20, 2015 Thunderstorms 3,906 57% 11 h 5.0 h 13k
Mar 24, 2018 No storm report 2,039 30% 5.2 h 2.0 h 9.3k
Mar 6, 2017 Thunderstorms 1,519 22% 7.5 h 6.8 h 8.4k
Jul 15, 2024 No storm report 5,442 79% 7.5 h 1.0 h 7.9k
Jan 10, 2020 Winter storm 1,627 24% 18 h 9.2 h 7.4k
Sep 8, 2020 No storm report 4,656 68% 1.5 h 1.0 h 7.0k
Jun 29, 2023 Thunderstorms 3,583 52% 4.8 h 1.0 h 6.2k
Oct 29, 2019 No storm report 1,539 22% 3.5 h 4.8 h 4.6k
May 13, 2018 No storm report 2,899 42% 3.8 h 12 min 4.5k

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 +2h 90% by +4h

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 Jefferson from twelve hours before it began to its peak. Matching shows coincidence, not proof of cause.

  • No storm on record 78%
  • Thunderstorms 9.5%
  • Winter storm 8.4%
  • Windstorm 1.8%
  • Ice storm 1.7%

Who keeps the lights on

Utilities serving Jefferson

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
Interstate Power and Light Co Investor Owned 89 74 0.82 17.8 419k
T I P Rural Electric Coop IA 156 156 1.33 11.9 82k
Access Energy Coop Cooperative 83 83 0.77 14.8 8.9k

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 6,879 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 →