After parts of Alberta got a decent snowy blast to end the week, it will be Manitoba’s turn for a coating of the white stuff during the second half of the weekend. While most of the Prairies will be quite quiet for the first week of November, thanks to a stationary ridge centred over Alberta, it will be a different story for southern Manitoba and northwestern Ontario as a result of the setup. Halloween will be ghoulish for some, with chilly temperatures and lake-effect snow pushing in. Some areas will be on the hook for 5-10 cm of snow, as it will be sticking around through Monday, as well. More on the timing and impacts, below.
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SUNDAY/MONDAY: SNOWY, CHILLY HALLOWEEN AND START TO NOVEMBER
The ridge over Alberta will team up with a broad upper-level trough over Eastern Canada to funnel Arctic air into Manitoba and northern Ontario. Temperatures of -10°C to -15°C at roughly two kilometres altitude will draw ample moisture from the relatively warm waters of central Manitoba and northern Ontario.
As a result, lake-effect snow will move into southern Manitoba and northwestern Ontario Sunday morning.
The north-northwesterly winds will drive the lake-effect squalls into the Winnipeg region and intermittently impact the Trans-Canada Highway from Portage La Prairie, Man., to the Ontario border, along with Highway 11 and 17 in Ontario from Lake of the Woods to Lake Superior.
Most areas will just see a cm or two but the southeastern shores of lakes Winnipeg, Manitoba, Seul, Nipigon and Lake of the Woods could see 5-10 cm locally. The bands of snow will linger through Monday.
Temperature-wise, Halloween and Monday will be rather brisk, with far-reaching single-digit highs on both days as the chilly airmass remains hovered over the province.
LOOK AHEAD: REMAINING COLD THROUGH MID-WEEK
Temperatures will stay quite chilly in Manitoba through the middle of next week. Widespread high temperatures in the lower single digits are anticipated, dropping well below freezing at night.
The pool of cold air will shit over the Great Lakes by Tuesday.
However, warmer weather will reach Manitoba and northwestern Ontario by the weekend, and the second week of November will feature above seasonal temperatures across both provinces.
Be sure to check back for the latest updates on the weather across Manitoba and northwestern Ontario.