Drastic temperature flip in store across Canada

The first part of June delivered a taste of summer across parts of Canada, but with the season's official start still a week away, a significant weather shift is set to change the pattern from coast to coast.

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This weekend, an upper-level trough becomes stalled over northern Ontario and western Quebec, thanks to a blocking ridge in Greenland. This setup will lead to cooler-than-normal conditions in the east, while heat builds in the west.

An upper-level ridge will settle over western Canada this weekend, creating dry and warm conditions. Temperatures along the B.C. coastline are forecast to rise 6°C-11°C above seasonal norms. The ridge will peak on Sunday, extending its influence into the Yukon and Northwest Territories.

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Alberta will see near-seasonal temperatures, but Saskatchewan and Manitoba will trend below average. A cold front moving through on Thursday will allow cooler air to settle in. Meanwhile, a low pressure system retrograding into northern Ontario and Manitoba will funnel in dry, cooler air from the Prairies towards the east.

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Ontario and Quebec will experience below-seasonal temperatures beginning late Sunday, as a low pressure system brings a risk of thunderstorms.

The associated cold front will usher in cooler air, with unsettled conditions lingering into the start of the next week as the trough remains over the region.

Atlantic Canada faces variable conditions next week as the influence of an upper-level ridge and the Ontario-Quebec trough shifts, delivering alternating wet and dry periods.

Prepare for these changing conditions as temperatures fluctuate and weather patterns shift across the provinces.