Mainers who awake Sunday morning to find that they’ve lost power to their homes might be in for a long wait to have their electricity restored, utilities in the state warned.

As of late Saturday evening, the National Weather Service had expanded its ice-storm warning to include densely populated areas much closer to the Maine coast, including Portland.

The expanded warning greatly increased the risk of widespread power outages, a meteorologist at the weather service’s office in Gray said.

Meteorologist Mike Kistner said at least a half-inch of ice was forecast for nearly the entire state. Only York and Aroostook counties were not expected to receive a significant amount of ice, he said. Kistner noted that Augusta and Bangor were predicted to be among the hardest hit of the larger cities, with up to an inch of ice.

“Now we’re looking at a large area of significant icing,” Kistner said. “It looks like the capital region could be hit very hard.”

The storm was not expected to produce as much ice as the devastating 1998 storm, which left up to 2 inches of ice in some areas.

However, Kistner said the amount of ice expected from the current storm would be enough to knock down power lines in many areas.

Central Maine Power Co. spokesman John Carroll said a half-inch of ice is generally the amount at which trees and power lines begin to fall, although it’s not a hard-and-fast rule.

“What we’ll be looking for is where the ice starts to exceed a half an inch,” he said, adding that slight changes in temperature can affect the behavior of ice-coated objects significantly.

CMP had scheduled 170 line workers for Sunday morning’s shift, along with 250 additional contractors from the U.S. and Canada who began working Saturday night, Carroll said.

“We’re as ready as we could be,” he said.

Still, roads become treacherous during an ice storm, and that slows down repair efforts, Carroll said.

One thing repair crews probably will not have to contend with is a large number of other motorists on the road, according to Maine State Police spokesman Stephen McCausland.

“I expect few of them will be on the road if the ice is in fact as bad as expected,” McCausland said.

Another reason repairs could be slowed is that utility crews must wait until the ice has melted or been cleared, and the risk of recurring damage has subsided, before they can go to work.

“You could fix something and have it break again,” Carroll said.

Similarly, Bangor Hydro Electric Co. was warning its customers to prepare for the possibility of going a long time without power.

“Customers are encouraged to prepare for the possibility of extended outages, should predictions of up to three-quarters of an inch of ice materialize,” the company said on its website, bhe.com.

In Augusta, Maine health officials were reminding residents not to run gas-powered generators in basements or garages if they lose power in the ice storm, The Associated Press reported.

Maine Centers for Disease Control officials said running gas-powered generators in the basement or garage is dangerous because they can produce as much carbon monoxide gas as 100 idling cars, according to the AP. Officials said to always use generators outside and place them at least 15 feet away from windows and doors.

As of late Saturday, temperatures were trending colder, leading the weather service to predict that ice could form on the ground as early as midnight Saturday.

The ice storm was expected to hit a number of densely populated urban centers, Kistner said.

“It’s not like this is hitting in (just a) rural part of the state,” he said. “We’re expecting a lot of power outages.”

Carroll said CMP officials were hoping the company’s massive outage-repair team would not be necessary, and that the storm would be milder than expected.

Either way, the effort would be a learning experience, he said.

“The storm response is a big machine, and every time we get it cranked up, we learn something,” Carroll said.

J. Craig Anderson can be contacted at 207-791-6390 or:

canderson@pressherald.com

Twitter: @jcraiganderson