United Illuminating Co. and Eversource Energy officials said Thursday that their customers should prepare for post-storm power restoration efforts to take at least several days.

Several hundred repair crews with both utilities are working around the clock to restore electricity after the second nor’easter in a week dropped wet, heavy snow on trees, which subsequently knocked out power. At the peak of the storm, Orange-based UI had 36,500 customers without power and while Eversource officials weren’t offering peak outage data, officials estimates put the number at over 124,000.

In addition to power outages, thousands of residents in the Greater New Haven area woke up to trees down and closed roads Thursday, after what the National Weather Service said was 4 to 13 inches of snow that fell Wednesday and overnight. many schools also were closed.

“Right now, we’re calling it a multi-day restoration effort,” said Mitch Gross, an Eversource spokesman. “We’ve restored around 80,000 customers since mid-day Wednesday. But in many places, particularly in Fairfield County, our restoration efforts are being hampered by trees across roadways that are keeping our crews from getting to places where the problems are.”

Michael West, a spokesman with UI, said the utility has 300 workers devoted to the repair effort. West said the company arranged on Thursday for additional help from Midwestern utilities.

“They are probably a day and a half away,” he said. “Our work is progressing nicely. We’re under 10,000 customers without power and as we have more time to assess the problem, we’ll determine if we still need them here or whether they can be released to go elsewhere.”

West said the restoration effort will take a minimum of two days for UI.

“If we can fully restore more power quickly and safely, we will,” he said. “But based on the information we know now, this is what we are telling people.”

Dana Durant, who lives on Olive Street in New Haven, said he lost power around 9 p.m. Wednesday, but it came back on at 3 a.m. He said he snuggled with his dog under an extra quilt, as “it was starting to get cold in (his) apartment.”

Durant said he read with a flashlight before going to bed and woke up around 3 a.m. when his kitchen lights came back on.

Ian Guthrie, who lives on Court Street in New Haven, said Thursday morning that he hadn’t had power since 8 p.m. Wednesday. He said he lit 35 tealights, strategically placed around his apartment, before going to bed.

“There was a really big bright flash, right past the train tracks. Then the street light started blinking red and then went out,” Guthrie said.

When Guthrie went to bed Wednesday night, the temperature in his apartment was 66 degrees, but upon waking up discovered it had dropped to 58 degrees. He said he was on his way to find some place warm, and that had Wi-Fi, to get work done.

Gross said the first priority for Eversource after a power outage is to restore power to nursing homes and hospitals as well as other emergency facilities. Even while that is going on, the utility is working on other restorations and meeting with leaders in the communities it serves to determine if their are any local priorities in terms of getting the power back on, he said.

“It’s a multi-faceted approach,” Gross said.

Eversource still had contractors and mutual aid crews from out-of-state utilities working on the most difficult outages from last Friday’s storm as Wednesday’s nor’easter approached. That turned out to be a blessing in disguise, given the severity of the second storm, according to Gross.

“If they had not already been here, restoration effort now would be much, much more challenging,” he said.

Ellen Swanson-Katz, Connecticut’s Consumer Counsel, took the unusual step of taking to social media to urge customers be patient with the restoration efforts. Katz, who represents ratepayers in utility cases that are heard by state regulators, said Eversource officials had told her that some of the most problematic outages could take a week or more to repair.

“Trees down everywhere,” Katz tweeted. “Please support utility line workers who have been working nonstop from last week’s storm & now this one.”

Not everybody is willing to be so patient. Lon Seidman, a small businessman from Essex who serves on the town’s Board of Education, called Eversource’s performance in restoring power “business as usual.”

“They used to have a much larger staff to customer ratio,” Seidman said. “Given the frequency of these events — about once a quarter now -- it would be warranted (to restore larger staffing levels). With the company earning just shy of a billion dollars in profit last year they can afford it.”

Eversource is putting the burden of communicating on local officials and not doing better at it themselves, he said.

“There’s simply no competitive reason for them not to disclose what staffing levels they have to address these events and prepare for others,” Seidman saod. “The only reason I can see is that it would detail deficiencies that equal more profits for them and less service for customers.”

Director of Emergency Operations Rick Fontana said the parking ban in the downtown area has ended, but the residential ban — cars can only park on the even side of the street — was in effect until 8 a.m. today.

“We’re doing this for almost an additional 24 hours, so we can get good headway in the smaller residential streets. I think it will make a huge difference,” he said.

Residents experiencing a snow-related issue are urged to call the Emergency Operations Center at 203-946-8221 instead of 911, he said.

State police on Thursday said that during the duration of the storm, from 11 a.m. Wednesday to 7 a.m. Thursday, troopers responded to 1,526 calls for service. There were 166 accidents without injuries, six accidents with injuries and 565 motorist assists on state roads, state police said.