Power Out Map
– 0% of Suffolk out 0 customers out in Massachusetts

Power outage history

Suffolk County Massachusetts

1.7hours

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

14th most of 14 in Massachusetts 75% below the national median

Worst outage on record Dec 18, 2023 3% of customers out · 90% back in 22 hours
Hours without power, average customer per year 1.7h / yr State average 5.7 h · national median 6.6 h
Major outages a year 0.0 Peaks over 10% of customers or 50,000 customers
Typical time to restore 90% – Median across major outages, from the peak
Longest single outage 14hours Dec 18, 2023, over 1% of customers out
Outage hours on storm days 47% Share falling on days with a NOAA storm report here
Worst year 2018 2.5 hours without power, average customer
Electricity customers 407,092 Estimated from population · 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 Suffolk'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

2018 was the worst well-recorded year, at 2.5 hours for the average customer. Hatched years have a thin record and are left out of the averages.

Suffolk, hours without power per customer

SuffolkUS median countyMassachusetts average
0 2 4 6 8 1.6 ’15 1.8 ’16 1.5 ’17 2.5 ’18 1.3 ’19 1.6 ’20 1.5 ’21 1.4 ’22 1.7 ’23 1.3 ’24 2.0 ’25 US 6.6 MA 5.7

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 18, 2023 Windstorm 12,487 3% 14 h 22 h 100k
Oct 17, 2019 Windstorm 9,193 2% 8.0 h 15 h 58k
Mar 2, 2018 Windstorm 11,082 3% 12 h 22 h 57k
Jun 24, 2025 No storm report 10,041 2% 8.8 h 14 h 56k
Jul 24, 2022 No storm report 19,604 5% 3.0 h 3.0 h 26k
Jul 29, 2025 No storm report 18,010 4% 2.8 h 2.5 h 25k
Nov 3, 2023 No storm report 15,082 4% 1.8 h 1.8 h 23k
Feb 25, 2019 Windstorm 6,936 2% 4.5 h 4.8 h 23k
Jun 20, 2025 No storm report 6,655 2% 3.2 h 1.0 h 22k
Jul 6, 2015 No storm report 10,428 3% 2.0 h 2.0 h 20k
Jul 20, 2023 No storm report 8,775 2% 2.5 h 1.2 h 19k
Oct 27, 2021 Tropical Storm Wanda 5,145 1% 6.2 h 5.2 h 16k

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

  • No storm on record 53%
  • Windstorm 42%
  • Tropical storm 3.0%
  • Winter storm 1.2%
  • Thunderstorms 0.5%

Who keeps the lights on

Utilities serving Suffolk

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

Utility Type Outage min / yr Excl. major storms Outages / yr Residential ¢/kWh Customers
NSTAR Electric Company Investor Owned 113 66 0.81 21.5 1.3M
Massachusetts Electric Co Investor Owned 133 91 1.00 33.7 1.2M
Massachusetts Bay Trans Authority Political Subdivision – – – – –

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 Massachusetts

Where it is darkest

Hours / yr64+

All Massachusetts 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 407,092 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 →