Environment and Climate Change Canada can't predict how deep the snow will be this winter or when the next storm will hit, but it can estimate the general weather anticipated for the next three months.
"One clue this winter is that a weak La Niña is expected to play a role," said Jennifer Smith, a national warning preparedness meteorologist, during a Dec. 12 media briefing.
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La Niña is a climate pattern in the Pacific Ocean and can affect weather worldwide. By pushing cold water toward Canada and the United States, it usually brings cooler than normal temperatures across Canada.
This is the fifth La Niña event in the last six years.
ARTICLE CONTINUES BELOW News What's a 'La Niña winter' and what does it mean for Canada's winter weather this year? Evelyn Harford
Smith noted this fall was mild across most of Canada, which made the abrupt start to winter feel much colder than in recent years.
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So far this December, temperatures in southern Ontario have been slightly cooler than normal, which is in line with a weak La Niña.
ARTICLE CONTINUES BELOW Will Canada's winter be on the mild side?
Looking ahead for the rest of the winter months, Smith said above-average temperatures are forecasted for the northeastern Arctic communities, including Hudson Bay.
Cooler temperatures are expected in the Yukon, Northwest Territories and Nova Scotia this winter.
But in Ontario, there was limited information on the overall temperature outlook, with equal chance it could be cooler than normal, warmer than normal or just average.
"Day to day, Canadians will still experience the full range of winter weather, from those bone-chilling cold snaps thanks to the less stable polar vortex, along with milder temperatures drawn in."
Will precipitation be above average? ARTICLE CONTINUES BELOW
With a weak La Niña in place, storms will typically track diagonally from the Yukon, into the Rockies and down into the western Great Lakes, Smith said.
"That classic storm pathway is where we lean above-average for total precipitation this winter," she said. "Further east, things are less clear."
Areas around the Great Lakes started the winter season warmer than usual, which provides an opportunity for moisture to fuel snow squalls, she added.
"Those events are highly localized but can be intense -- especially early in the season."
So far, there wasn't enough data collected to predict if southern Ontario will see more than average precipitation, but western parts of the province are expected to have more snow or rainfall this season.
Ontario's winter storms ahead
When asked to share southern Ontario's upcoming winter predictions, Smith noted there wasn't sufficient data to say if it will be colder or warmer than normal.
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She did say last week's storm caused by Alberta clippers headed across the country tracked along a classic path, which encompassed southern Ontario.
"It's called a clipper because it forms on the east side of the Rockies in Alberta and then it zips along at a good clip," Smith said. "It doesn't usually cause a large amount of snowfall but it did (this time).
"You can't guarantee every storm that works its way along the western Great Lakes is going to pass along southern Ontario," she said. "The bigger thing for southern Ontario (right now) is the Great Lakes are wide open. We've got a great potential for snow squalls -- I know that doesn't necessarily reach Toronto -- but there's a lot of potential for a lot of precipitation, especially snowfall, in the early part of the season."
Until the lakes start to freeze over, Ontario is likely to see more snowfall events, she added.
"I wouldn't be surprised to see more (Alberta clipper-type events) through the winter, I just don't know how many," Smith added.
Other weather watchers, such as The Weather Network and the Farmer's Almanac, have predicted a "true Canadian winter" across the country.
News Get ready for a 'true Canadian winter' across Canada, The Weather Network predicts in winter forecast Janis Ramsay ARTICLE CONTINUES BELOW Tracking climate change
Along with the winter outlook, Environment Canada staff said it has been tracking climate change to estimate our industrialization on the weather events.
Between 1948 and 2025, there has been a warming trend, with the average winter temperatures rising by 3.7 C across the country.
"This warming trend is always the backdrop of any seasonal winter forecast, partially offset by La Niña," scientist and researcher Madalina Surcel said.
She added Environment Canada predicts the likelihood of extreme precipitation events are expected to be more frequent and more severe, due to human-caused climate change.
Using testing models, the average wettest days in Ontario are now expected to have between 30 to 40 millilitres of rainfall.
Extreme weather events more likely ARTICLE CONTINUES BELOW
One new tool in use is Environment Canada's Rapid Extreme Weather Event Attribution system.
Scientists can now calculate if serious temperature extremes are more or less likely because of climate change.
The system shows our winter cold snaps are less likely to occur in today's climate, while heat waves and extreme rainfall are more likely to happen.
This past summer, Environment Canada expanded the program for precipitation events.
"Since June 2025, researchers have analyzed 42 of the most extreme precipitation events across Canada and determined that 39 were made more likely to occur by human-caused climate change," Environment Canada said on its website.
Another three were much more likely to happen from climate change.
For more information about Environment Canada, visit weather.gc.ca.
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