PORTSMOUTH - A spring storm that dumped wet, heavy snow on the Seacoast also resulted in tens of thousands of power outages.

Utility representatives were advising people to prepare for the possibility of a night without power because the range of outages was too great for all power to be restored on Thursday.

Public Service of New Hampshire spokeswoman Mary-Jo Boisvert said at about 10 p.m. Thursday, 17,000 customers remained without power, down from a peak of 56,000.

About 3,600 residents in Epping, Lee and Newmarket were still without power as of press time. Boisvert said crews were expected to restore that power by tonight. The Rochester and greater Epping areas were the hardest hit, said Boisvert. About 10,000 in Rochester remained without power, she said.

Martin Murray, spokesman for Public Service of New Hampshire, said Portsmouth had about 1,700 people without power. He said one block of about 100 people in the city had no one working on the problem as of 1 p.m.

"We have more than 200 crews out, some imported from our sister utilities in Connecticut and Massachusetts," said Murray. "We hired some independent contractors that sometimes work with us. We'll leave some out tonight and rest others so we can put a large work force out first thing in the morning."

Central Maine Power spokesman John Carroll said about 80,875 were still in the dark Thursday night "" down from a peak of 117,000. In the Alfred Service Center, which serves York County and a small portion of Cumberland County, about 31,550 homes were still without power, down from about 45,000 earlier in the day.

Carroll said he expected power to be restored in Kittery and York today. Power in the Berwicks may not be restored until Saturday, he said.

Carroll said this storm was the utility's first this winter and spring with significant outages. "The temperature was warm, and the snow wet and sticky," he said. "It really loaded the branches. They sagged down and took the wires down."

Central Maine Power was fully mobilized with 240 crews in the field, including tree crews, line workers and people setting poles.

Unitil spokeswoman Stephanye Schuyler said about 8,000 customers were without power during the peak of the storm, but that power to all but 125 homes had been restored Thursday night.

"About 20 of those are in the Seacoast," she said.

She said spring storms are always among the worst. "It poses a great challenge," she said. "You get snow loading, and then trees and branches fall on the wires. Sometimes the power goes out again as soon as you fix a problem."

Police in many towns were kept busy overnight on Wednesday and Thursday.

Kittery, Maine, Police Chief Edward Strong said by late afternoon there were still a few thousand people without power.

"We have a call into CMP now, and if the power will be out all night, we're looking at opening up an emergency shelter at the Shapleigh School because it has a generator," Strong said. The town did not open a shelter Thursday night.

Strong said police responded to quite a few accidents.

"We had about 170 calls for service since 7 a.m.," he said. "It was a freak storm that caused a lot of damage."

He said power had been out for about 15 to 16 hours at that point, but that roads were clean and accidents were no longer an issue.

York still has a lot of places without power, said spokeswoman Virginia Avery. She said there were a few minor accidents in the morning.

The power was still out in Greenland, said Police Chief Michael Maloney.

"We still have some lines down," he said. "On Bayside Road, we have live wires across the road. We had to block the road off and put someone down there."

Maloney said there were a couple of accidents Wednesday night, including one rollover. Most were just cars off the road that had to be towed out.

Rye police reported no problems.

Staff reporter Susan Nolan contributed to this report.