Power Out Map
– 0% of Hamilton out 0 customers out in Tennessee

Power outage history

Hamilton County Tennessee

1.8hours

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

62nd most of 73 in Tennessee 72% below the national median

Worst outage on record May 9, 2024 12% of customers out · 90% back in 33 hours
Hours without power, average customer per year 1.8h / yr State average 5.8 h · national median 6.6 h
Major outages a year 0.1 Peaks over 10% of customers or 50,000 customers
Typical time to restore 90% 33hours Median across major outages, from the peak
Longest single outage 37hours May 9, 2024, over 1% of customers out
Outage hours on storm days 76% Share falling on days with a NOAA storm report here
Worst year 2024 5.0 hours without power, average customer
Electricity customers 187,870 ORNL customer model · 7 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 Hamilton'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

2024 was the worst well-recorded year, at 5.0 hours for the average customer. Hatched years have a thin record and are left out of the averages.

Hamilton, hours without power per customer

HamiltonUS median countyTennessee average
0 2 4 6 8 ’17 ’18 0.2 ’19 0.3 ’20 0.2 ’21 0.4 ’22 2.2 ’23 5.0 ’24 4.5 ’25 US 6.6 TN 5.8

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 9, 2024 Flooding 22,237 12% 37 h 33 h 325k
Jun 7, 2025 Thunderstorms 10,104 5% 28 h 29 h 161k
Jul 30, 2024 Thunderstorms 15,147 8% 19 h 20 h 111k
Aug 7, 2023 Thunderstorms 15,097 8% 14 h 15 h 65k
May 5, 2025 No storm report 4,869 3% 13 h – 62k
Mar 4, 2025 No storm report 5,044 3% 13 h 13 h 36k
Jan 12, 2024 No storm report 5,393 3% 7.5 h 11 h 30k
Jul 2, 2023 Thunderstorms 3,639 2% 9.0 h – 25k
Jul 1, 2023 Thunderstorms 4,453 2% 10 h – 22k
Apr 23, 2025 No storm report 2,702 1% 8.0 h – 21k
Mar 16, 2025 Thunderstorms 5,759 3% 6.0 h 8.8 h 20k
Jan 3, 2022 Winter storm 2,280 1% 8.0 h – 18k

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 +20h

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

  • Thunderstorms 41%
  • Flooding 31%
  • No storm on record 24%
  • Winter storm 1.9%
  • Tropical storm 1.2%

Who keeps the lights on

Utilities serving Hamilton

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

Utility Type Outage min / yr Excl. major storms Outages / yr Residential ¢/kWh Customers
City of Chattanooga Municipal 194 72 1.36 12.9 165k
Volunteer Electric Coop Cooperative 685 436 5.80 13.1 105k
Sequachee Valley Electric Coop Cooperative 305 253 2.15 13.8 33k

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 Tennessee

Where it is darkest

Hours / yr64+

All Tennessee 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 187,870 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 →