Power Out Map
– 0% of Johnson out 0 customers out in Illinois

Power outage history

Johnson County Illinois

4.9hours

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

45th most of 101 in Illinois 26% below the national median

Worst outage on record Jan 7, 2025 16% of customers out · 90% back in 27 hours
Hours without power, average customer per year 4.9h / yr State average 2.9 h · national median 6.6 h
Major outages a year 3.1 Peaks over 10% of customers or 50,000 customers
Typical time to restore 90% 2hours Median across major outages, from the peak
Longest single outage 4.0days Jan 5, 2025, over 1% of customers out
Outage hours on storm days 66% Share falling on days with a NOAA storm report here
Worst year 2025 12 hours without power, average customer
Electricity customers 6,500 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 Johnson'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

2025 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.

Johnson, hours without power per customer

JohnsonUS median countyIllinois average
0 5 10 15 0.8 ’15 1.9 ’16 1.9 ’17 4.6 ’18 3.1 ’19 1.9 ’20 2.2 ’21 1.3 ’22 3.0 ’23 11 ’24 12 ’25 US 6.6 IL 2.9

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
Jan 5, 2025 Ice storm 1,055 16% 4.0 d 27 h 41k
May 26, 2024 Tornadoes 1,873 29% 46 h 39 h 31k
Jun 28, 2018 Thunderstorms 2,467 38% 22 h 9.8 h 15k
Apr 7, 2024 No storm report 974 15% 20 h 19 h 11k
May 16, 2025 No storm report 671 10% 16 h 14 h 9.6k
Apr 2, 2024 Thunderstorms 1,248 19% 16 h 13 h 8.6k
Mar 15, 2025 Tornadoes 1,322 20% 21 h 9.2 h 8.3k
Mar 4, 2025 Windstorm 837 13% 16 h 1.8 h 7.3k
Sep 26, 2021 No storm report 322 5% 22 h – 7.0k
Jun 21, 2019 Thunderstorms 1,279 20% 11 h 4.5 h 5.6k
Jan 25, 2023 Winter storm 1,265 19% 7.5 h 5.2 h 5.6k
Jun 29, 2018 Heat 393 6% 20 h 21 h 4.8k

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 +16h

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

  • No storm on record 34%
  • Ice storm 18%
  • Tornadoes 18%
  • Thunderstorms 14%
  • Windstorm 6.0%
  • Winter storm 5.1%
  • Heat 3.2%
  • Flooding 1.1%

Who keeps the lights on

Utilities serving Johnson

As each utility reports to the Energy Information Administration for its whole Illinois territory, not this county alone. Outage minutes include major storm days.

Utility Type Outage min / yr Excl. major storms Outages / yr Residential ¢/kWh Customers
Ameren Illinois Company Investor Owned 287 130 1.19 16.7 1.1M
Southern Illinois Elec Coop IL 228 105 – 15.3 152k
Southeastern IL Elec Coop, Inc Cooperative 2,214 172 3.95 14.8 23k
Egyptian Electric Coop Assn Cooperative 773 24 4.62 16.2 14k

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 Illinois

Where it is darkest

Hours / yr64+

All Illinois 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 6,500 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 →