And Environment Canada says the Prairies will remain cold, but should get some clearer skies after blizzard-like conditions rolled across the region during the weekend before breaking Sunday night.
Ontario got a mix of warm and winter-like on Monday, with residents in the province's south ditching sweaters for lighter attire as temperatures in many municipalities reached the high teens, while Ottawa peaked at 20 Celsius.
Some parts of western Quebec also got a dose of higher-than-usual temperatures, with Montreal hitting 18 C — a likely record.
Those living in Ontario's north were advised to keep their snow shovels close at hand, as a special weather statement warned of up to 15 centimetres of snow on the heels of Sunday flurries.
Environment Canada says 10 municipalities in Ontario unofficially set heat records on Sunday, while a handful of places in the southern region, including Ottawa and Hamilton, appeared on the cusp of breaking records on Monday.
Environment Canada says the record-setting Remembrance Day warmth was triggered by the winter storm in northern Ontario which pulled warm air up from the Gulf of Mexico.
It forecasts that a chill will come in southern Ontario on Tuesday, as temperatures dip down to around freezing.
Light snow and sub-freezing temperatures greeted Prairie residents Monday after weekend snowstorms dumped more than 20 centimetres of snow in Manitoba, leading closure of a 150 kilometre stretch of the Trans-Canada Highway west of Winnipeg until mid-day on Sunday.
The storm system also delivered heavy snowfalls in southern Saskatchewan and much of Alberta, where the flakes were followed by -25 C wind chill.
The weather fluctuations shouldn't come as too much of a shock, said Beverly Archibald, director of True North Weather Consulting Inc., a specialized forecasting firm based in Edmonton.
"Canadians have to realize that there are always extremes in weather. We are very rarely right at normal," said the former Environment Canada meteorologist.
"We've seen that in Eastern Canada because of the frankenstorm (Sandy) and events of the last weekend compounding our idea that the weather has been quite unusual."
But Archibald said it's likely that when climatologists look back and parse the factors behind the recent weather patterns, they'll narrow things down to one main culprit — El Nino, a warming of surface ocean temperatures in the eastern Pacific.
By taking the big-picture view the recent shifts will appear relatively normal, she added.
"I think we'll look back and say this was quite a typical El Nino winter."
Archibald said there could be more of the same in store if El Nino sticks around throughout the remainder of fall and winter.
"It's probably going to be a continuation of the snowy pattern for Western Canada and for Eastern Canada these swings in weather — very cold, very warm, very cold, very warm — which would be typical of these variable weather patterns," she said.
"Depending on what side of the camp you're on in climate change, this is playing right into the climate change scenario where we'd see an increase in extreme weather events," she said.
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