Less than two weeks into winter, Canadians from coast to coast have been warned to prepare for true-to-form seasonal weather conditions this weekend.

Environment Canada is warning that a large winter storm system is moving from the U.S. into Ontario, Quebec, and Atlantic Canada this weekend. The storm will bring a roller coaster of temperatures to Ontario and Quebec that will include snow, ice pellets and rain.

The weather office has issued a special weather statement to say that a "significant winter storm" will hit southern Ontario Saturday.

The timing and amount of precipitation is uncertain, and conditions could change quickly, so those with weekend travel plans across Ontario and Quebec are being advised to prepare for "dangerous road conditions."

Environment Canada says the storm will begin sometime Saturday afternoon as snow, with between five and 10 centimetres falling on central and eastern Ontario and "heavy snowfall" hitting most of Quebec.

Then, as temperatures rise to as high as double digits in some areas, the snow will transition to rain by Saturday night or Sunday.

Freezing rain and ice pellets are likely during the transition, and may be especially bad in areas northwest of the Golden Horseshoe (between Niagara Falls and Oshawa). The Ottawa Valley is also expected to be hit hard by the snow and rain.

By Sunday night, temperatures will plummet again and then stay low for the rest of the week.

As the temperature drops Sunday night, residents across most of southern and eastern Ontario can expect strong winds and flurries.

In northern Ontario, the same storm system is expected to bring a steady snowstorm that will extend from the Manitoba border to Quebec.

Storm headed east

Further east, the storm system should hit Atlantic Canada by Sunday, bringing 10 to 15 centimetres of snow in the morning and then changing to ice pellets or freezing rain later in the day.

A similar pattern will begin in Newfoundland later Sunday, with heavy snowfall expected in the afternoon, changing to ice pellets, drizzle and strong winds by Monday morning.

Environment Canada is advising Atlantic residents to monitor future forecasts for further warnings about this storm.

Alberta snow

Meanwhile, parts of western and central Alberta received close to 10 centimetres of light snowfall Friday.

Drivers are being warned that visibility may be reduced at times while roads, walkways and parking lots may become difficult to navigate because of the snow.

Pacific Coast

And in British Columbia, a high pressure system over Yukon will send a dose of frigid air south and west through the B.C. Interior. That cold front should run into a moisture-packing Pacific warm front, creating a messy "montage of rapidly changing winter conditions," Environment Canada says.

Vancouver could get as much as 30 centimetres of snow before 40 to 50 mm of rain falls Sunday, followed by another 30 to 40 mm on Monday.

In the mountains of Whistler, that precipitation will come in the form of 20 cm of snow on Sunday, followed by 10 to 15 of rain on Monday.