Winter Storm Grayson caused a loss of power for 90,000 Dominion Energy customers in areas of Virginia and North Carolina, but the company had restored the vast majority of them by 12 hours after the storm ended, the company said.

High winds of almost 60 miles per hour knocked down trees and tree limbs, which pulled down power lines, producing the main cause of power outages, according to Bonita Billingsley Harris, spokeswoman for Dominion Energy.

Snow- and ice-covered roads impeded travel to some areas that needed power lines fixed. There were crews at 550 separate locations that required damage to be fixed, and the crews worked around the clock to restore power as soon as possible, Harris stated.

“With the exception of Virginia Beach and hard-to-access areas of the Outer Banks, Dominion Energy crews restored power to all customers back by 11 p.m. Thursday night, with the rest of our customers back on by 5 p.m. Friday,” Harris said in an email.

The cities of Virginia Beach, Chesapeake, Norfolk and parts of North Carolina were the most affected areas during the storm. About 80,000 customers were affected in those three cities, including 16,000 in North Carolina.

In Suffolk, only about 20 customers were affected, since the city suffered lower winds than areas closer to the coast, according to Harris.

The highest priority was given to hospitals, emergency 911 call centers, municipal water pumping stations and other public safety facilities. By Thursday afternoon, 90 percent of those facilities had regained power.

Dominion Energy worked with the Virginia Department of Emergency Management, local officials and the Virginia Department of Transportation to ensure efficient restoration, according to a press release from Dominion Energy. Crews from Richmond and western portions of the state responded to Hampton Roads the day of the blizzard to aid in the restoration effort.