Polar vortex slides into Ontario this weekend bringing a big
After days of high record-breaking heat, autumnal weather will arrive this weekend across Ontario, with temperatures falling by more than 15°C in some areas
A piece of the polar vortex will begin to track over southern Ontario this weekend, bringing much colder temperatures and a sharp contrast to the record-setting heat felt earlier in the week.
Temperatures will be much more typical of late October and early November for Sunday and Monday, with blustery conditions, periods of rain, lake-effect showers and even waterspouts popping up over the weekend. Many places will see temperatures remain in the single digits on Sunday and Monday, bringing the threat for wet snow across sections of the northeast.
Despite the heavy rain that picked up through the overnight hours on Thursday, the weekend will not be a washout for southern Ontario. While we will see occasional showers, much of the time it won't be raining and there will be sunny breaks, especially on Saturday.
DON'T MISS: Polar vortex to replace Canadian heat with chill, snow
Autumnal weather arrives for the Thanksgiving long weekend
Areas: Southern and northeastern Ontario
Timing: Through the long weekend
Weather: Wet snow and possibly even a slushy coating of snow is forecast for parts of Ontario this Thanksgiving, as we plunge from record breaking July-like heat, to feeling like November in just a matter of days.
A sliver of the polar vortex trapped in a deep trough will drive snowfall potential for some, rain for others, as well as temperatures 5-10 degrees below normal for the province this long weekend.
This colder arctic air mass over the warmer waters of the Great Lakes is what sets up a temperature contrast, driving lake-effect precipitation.
The shores of Lake Huron and Georgian Bay are likely to see persistent rain showers on Saturday and Sunday. This weekend may offer ample chances for funnel clouds and waterspout sightings over the lakes as well.
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Northwesterly winds will also bring a much more definite autumn chill province-wide as this system stalls over the northeast, moving backwards rather than a typical eastward track.
By Sunday into Monday, temperatures will struggle to reach double digits, with Toronto's daytime high expected to be just at 10°C on Thanksgiving Monday.
Meanwhile, we will fail to reach the freezing mark in the northeast during the overnight hours, converting lingering rainfall into a rain-snow mix from Sudbury to Kapuskasing and the higher elevations of Algonquin. While exact accumulations are uncertain, we can expect a slushy coasting of the white stuff waking up on Thanksgiving.
Temperatures will trend closer to seasonal values in the mid-teens for mid and late next week, but with the potential for another system late next week or weekend.