Weather Network predicts this fall will start cold, end mild

Canadians can expect a "fickle fall" this year as the season is forecast to start off chilly before above normal temperatures lead the country into winter, a prominent forecaster predicts.

The Weather Network says winter may appear to taunt Canadians across the country as they face periods of very cold weather during the fall, but the season is expected to end on a mild note because a jet stream in the Pacific Ocean, called El Niño, is expected to be two degrees warmer than usual.

"Our forecast team at The Weather Network is seeing a fickle fall ahead for most Canadians, and it's all due to El Niño," chief meteorologist Chris Scott said in a phone interview.

"Generally in most El Niño falls, we get an early blast of cold weather in the middle of fall and as you're experiencing, it can be a bit of a slap in the face. But then the weather pattern flips over later in the season."

Scott said the forecast isn't the best for ski hills in British Columbia because the El Niño jet steam will persist from fall into winter "and that doesn't give the best pattern for getting a lot of snow in the mountains."

The fall forecast also doesn't help the wildfire season on the West Coast at the start of the fall because the atmosphere is expected to be drier than normal and significant rain isn't expected until the middle of the season, Scott said.

The Weather Network is also predicting that a few snowstorms will rage across the Prairie provinces in the middle of fall, cutting short the region's harvest season.

"However, as we flip towards the latter half of November into December, when we typically can get some of our coldest weather of the entire year ... it looks like the season should balance out to be slightly above normal in the Prairies," Scott said.

Similarly, Ontario and Quebec are expected to see a nasty push of cold air in October but winter is forecast to begin on a mild note, he said.

"We think the fall colours should be quite vibrant but things turn a little bit rotten and cold in the middle of October and will short circuit some of the really nice leaf-seeing time of the fall season," he said.

Ontario and Quebec are also expected to see less precipitation than normal, Scott added, and there may be some wind storms during the fall that cause power outages.

In Atlantic Canada, although early indicators show precipitation will likely be typical for the fall season, unpredictable storms that approach from the tropics could be a threat, The Weather Network said.

"We're really watching how tropical storms or hurricanes may come up the eastern seaboard and give a period of heavier rain for the Atlantic provinces," Scott said.

Temperatures are also expected to be typical in the Atlantic provinces, except Nova Scotia, which might see a hotter than normal fall, The Weather Network predicted.

In western Nunavut, Northwest Territories and Yukon, The Weather Network is predicting above normal temperatures.

Scott said precipitation should be above normal in the North as well, especially across western and central Nunavut and some parts of the Northwest Territories.

"It's all because of El Niño directing the weather patterns across the world," Scott said of Canada's fall forecast.

"The narrative of this fall is that we'll see this cold push in the middle of the season and then moderating towards the end."

This report by The Canadian Press was first published Sept. 13, 2023.