Margaret Murphy, a spokeswoman for Nova Scotia Power, said upwards of 9,000 customers had been in the dark early morning.
The majority of the outages were the Halifax area, but there were also outages in Parrsboro, Tatamagouche and Stellarton.
This weather system really started to pack its punch just before 6 a.m., this morning, that's what we're seeing, Ms. Murphy said.
The snow tends to be of a wet, heavy, sticky variety that accumulates on power lines, really builds up quite a crust on them, and then you get a little bit of wind behind that... can cause outages.
Utility crews were having to contend with slick road conditions, she said, but they hoped to have most outages repaired within a few hours.
However, a broken power pole in the Clayton Park area of Halifax was expected to take longer to fix.
(Crews) were prepared for the system for over 24 hours in advance, and we were in some ways prepared for it to hit hard last evening, but it didn't, she said. But we knew it was coming.
A number of schools across the province were closed because of the weather, including all schools under the Halifax Regional School Board.
In Fredericton and surrounding New Brunswick communities, crews were working to restore power to more than 3,000 customers after 15 centimetres of snow fell in the area.
Elsewhere in New Brunswick, hundreds of outages were also reported in Shediac, Sackville, Moncton, Sussex and Rothesay.
At the height of the storm Sunday night, NB Power said 8,000 customers were plunged into darkness as crews scrambled to restore power.
We were certainly affected last evening and probably to some extent today by road conditions, said Heather MacLean, a spokeswoman for the utility.
Certainly the winds will not help, and because there are so many separate incidents and the geographic area is more spread out, that's a challenge that we're facing.
Ms. MacLean said power crews from across the province were helping workers in Fredericton.
Kim Griffin, a spokeswoman for Maritime Electric in PEI, said there were no power outages reported on the Island.
However, some schools on the Island were closed.
The RCMP, meanwhile, advised drivers to take it slow the morning after the storm.
Highways in parts of Nova Scotia were described as snow-packed with black ice.
RCMP are asking the public to give themselves lots of extra time when travelling to work today, the Mounties said in a news release.