Mother Nature may throw a wrench into many Canadians' plans on one of the busiest travel periods of the year, as a messy mix of weather, including a potential major ice storm, is expected across the country starting today and through the weekend.

Environment Canada has posted warnings and special weather statements for much of southern and eastern Ontario, southern and central Quebec, New Brunswick, Prince Edward Island and Nova Scotia.

"This is kind of the precursor to a really juicy storm system that's already developing over Texas, [and which is] already starting to shoot in some snowfall in through New Brunswick and Prince Edward Island," said CBC meteorologist Michelle Leslie on Friday afternoon.

The system, which is forecast to move into Eastern Canada over the weekend, brings a widespread risk of freezing rain from southern Ontario all the way to sections of Nova Scotia.

Leslie said forecasters are concerned about a "severe weather outbreak" starting as soon as tomorrow that could affect 30 states, five provinces and over 100 million people in the U.S. and Canada. 

The storm system is expected to begin tracking north tomorrow, with Windsor starting to see rainfall after about 4 p.m. ET, Leslie said.

Freezing rain is also forecast for Toronto on Saturday, especially north of Highway 401. Ottawa and Montreal can expect ice pellets. 

There is potential for a major ice storm, Leslie added, with 20 to 30 millimetres of ice buildup starting later tomorrow.

"Overall best advice: stay off the roads,"  Leslie said, especially anywhere from Windsor through to Montreal late Saturday evening through the early hours of Sunday.

Ice can also form around power lines, causing power outages, cautioned CBC meteorologist Johanna Wagstaffe.

Another CBC meteorologist, Jay Scotland, also warned a "more potent storm" in certain regions is expected to hit Saturday night and into Sunday morning.

WEA Montreal Snowstorm 20131215

A motorist digs out his car after more than 20 centimetres of snow fell last week in Montreal. Eastern Quebec was warned to expect another 10 to 15 centimetres of snow this weekend. (Ryan Remiorz/Canadian Press)

"Sunday is going to be the day that we will see the bigger of the two storms moving into southern Ontario, southern Quebec and then continuing to push east to affect Atlantic Canada," he said.

"So that's the day you're really going to want to look ahead and make sure your flight is not cancelled or delayed, and allow extra time to get to the airports as traffic will be going very slow on Sunday."

Meanwhile, the Ottawa Valley and eastern Quebec was warned to expect another 10 to 15 centimetres of snow.

"There is a risk for widespread power outages due to fallen tree limbs and power lines," Environment Canada forecasters said. "For areas farther north, there is also the possibility for significant snowfall and ice pellets from Lake Huron eastward to the Quebec border."

Snow hits Calgary, Vancouver

Calgary broke records this month with the most snowfall seen in the city in over a century. 

More than 43 centimetres of snow has fallen over the month of December so far — the most in 112 years — with more snow expected to fall overnight. 

"It's not a heavy dumping of snow, but it is two to five centimetres and that could cause problems, especially on the Deerfoot Trail," said Leslie.

Meanwhile, several centimetres of snow hit the Vancouver area Friday morning, snarling the morning commute.

Environment Canada warned some areas could face as much as 10 centimetres of snow and temperatures hovering near the freezing mark.

WEA Atlantic Snow Storm 20131215

The latest storm is expected to dump up to 30 centimetres of snow in some regions of Central Canada and the Maritimes. (Andrew Vaughan/Canadian Press)

"We've seen some pretty decent accumulations by certainly Vancouver standards," Scotland said.

"This would be a lot of snow for folks driving around the city there today. Seven centimetres on the ground at the airport, at YVR in Vancouver. As we look a little further south and west ... [In] Victoria, 12 centimetres of snow being reported there. This is a part of the country where folks do not even own all-season tires on many vehicles, let alone winter tires. So messy conditions there."

Areas of the Fraser Valley, Sunshine Coast and Vancouver Island are also subject to snowfall warnings, with as much as 15 centimetres expected to fall in higher terrain.

In north and central B.C., eight to 10 centimetres of snow is expected with colder temperatures. Showers are expected on Saturday with warmer temperatures and rain in the forecast for Sunday.

Frigid conditions will continue in the Prairies Friday with temperatures reaching –25 C. A mixture of sun and cloud is expected on the weekend with a possibility of light flurries as the chilly temperatures remain.

A windchill warning has been issued in northern Manitoba, with windchill feeling like near –50 through to Saturday.

"This is a warning that extreme wind chill conditions are imminent or occurring in these regions," said Environment Canada. "At these extreme wind chill values, frostbite on exposed skin may occur in five to 10 minutes."

Busiest travel day

The weather is likely to affect travel plans on what is expected to be the busiest day for travel in the country.

Air Canada has already waived its penalty fees for customers on affected flights to re-book tickets.

WestJet and Air Canada have both issued travel advisories for airports they expect to be affected by the weather, including:

  • Toronto's Pearson International and Billy Bishop airports.
  • Montreal's Pierre Elliott Trudeau International Airport.
  • Ottawa's Macdonald-Cartier International Airport.

Airport officials are advising travellers to check their flights online before heading to the airport. "With this weather, we are seeing a number of delays [and] the number of delays is actually growing," said CBC reporter Tim Weekes. 

Travellers are also being told to allow extra time to get to the airport in case they are delayed on the road.