A snowplow clears streets in downtown Halifax on Saturday. (CBC)

A storm is battering most of the Maritimes, wreaking havoc on travel and power lines.

Snow, ice pellets, freezing rain and rain have been falling most of the day in Nova Scotia, New Brunswick and P.E.I., creating treacherous road conditions in some areas.

High winds are also being experienced right across the region, resulting in blowing snow and whiteouts.

No major accidents have been reported, but RCMP on Saturday reminded motorists to drive carefully.

Confederation Bridge officials were restricting certain types of vehicles from crossing the bridge linking Prince Edward Island and New Brunswick, effective 6:30 p.m. local time, due to high winds. The restrictions apply to high-sided vehicles, including trucks, tractor-trailers, recreational vehicles and buses, as well as automobiles towing trailers and motorcycles. Restrictions were expected to remain in effect until about 7 a.m. Sunday, officials said.

Bridges in the Halifax-Dartmouth area could be closed, said Alison MacDonald of the Halifax-Dartmouth Bridge Commission

"Between 95 to 100 km/h of sustained wind gusts, that's when we would consider closing the [A. Murray] MacKay bridge … and the [Angus L.] Macdonald bridge, around that same time as well," she said.

High-sided vehicles will be turned away from the bridges as soon as the wind hits 75 km/h, she added.

Flights and ferries cancelled

Several flights have been cancelled or delayed in Halifax and the New Brunswick cities of Moncton, Fredericton and Saint John.

Some ferry services have also been suspended for the day, including runs between Deer Island and L'Etete in New Brunswick.

As of 7 p.m., local time, NS Power was reporting that nearly 17,000 customers across the province were without electricity.

In New Brunswick, about 7,000 customers had their power knocked out, primarily in the Moncton area.

Extra crews and contractors were on call to deal with the situation.

Environment Canada's snowfall, wind and storm surge warnings remain in effect.

Up to 60 centimetres of snow is expected to fall in parts of New Brunswick and as much as 30 centimetres was in the forecast for parts of Nova Scotia.

Wind gusts of up to 100 km/h are expected in all three provinces, with the west side of the Cape Breton Highlands expected to see the worst of it with winds gusting 160 km/h.

The combination of high astronomical tides, storm surge and large pounding waves could also result in coastal flooding and could damage infrastructure along the Atlantic shoreline and Northumberland strait Saturday night during high tide, according to Environment Canada.