Suffolk CountyPower Outage History
What this grade means
Average — typical outage frequency and duration nationally. This county sits in the middle of the national distribution — its outage frequency and duration over the past 12 years are close to the nationwide median, neither notably better nor worse than most other US counties. A typical amount of backup-power preparedness is reasonable here.
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Feb 2, 2025 | <1 hr | 599,357 (91%) | Unnamed event |
| Aug 4, 2020 | 228 hrs | 197,669 (30%) | Tropical Storm Isaias |
| Jul 13, 2019 | 6 hrs | 77,275 (12%) | Unnamed event |
| Jun 30, 2019 | 58 hrs | 55,387 (8%) | Thunderstorm Wind |
| Aug 23, 2019 | 61 hrs | 40,156 (6%) | Thunderstorm Wind |
Was There an Outage on a Specific Date?
Pick a date to see whether a power outage was recorded for Suffolk County, New York that day.
Over the 11 years from 2015 to 2025, Suffolk County recorded 5,904 distinct power outage events, averaging 1.6 hours per event.
The single worst outage on record in Suffolk County started February 2, 2025, lasting less than 1 hour and leaving up to 599,357 customers without power (91% of the county) at its peak.
July has historically been the worst month for outages in Suffolk County, with 782 events recorded during that month across the dataset.
Based on this history, Suffolk County earns a Reliability Grade of C, placing it in the 52nd percentile nationally for grid reliability (higher percentile = more reliable).
Similar counties in New York
Counties with the closest reliability grade and national percentile to Suffolk County.
| County | Grade | National percentile |
|---|---|---|
| Chemung County | C | 54th |
| Nassau County | C | 51st |
| Jefferson County | C | 51st |
| St. Lawrence County | C | 55th |
| Clinton County | C | 55th |
Most reliable counties nationally
The top 3 counties nationally by reliability grade and percentile.
| County | State | Grade | National percentile |
|---|---|---|---|
| Clay County | South Dakota | A | 100th |
| Clearwater County | Minnesota | A | 99th |
| Limestone County | Alabama | A | 99th |
Least reliable counties nationally
The bottom 3 counties nationally by reliability grade and percentile.
| County | State | Grade | National percentile |
|---|---|---|---|
| Clay County | West Virginia | F | 0th |
| Lincoln County | West Virginia | F | 0th |
| Cameron Parish | Louisiana | F | 0th |
FAQ
How often does power go out in Suffolk County?
Between 2015 and 2025, Suffolk County recorded 5,904 outage events, averaging 1.6 hours each.
What is Suffolk County's reliability grade?
Suffolk County has a Reliability Grade of C, in the 52nd national percentile.
What was the worst power outage in Suffolk County?
The worst outage on record started February 2, 2025, lasting less than 1 hour and affecting up to 599,357 customers.