10-25+ cm: Potent snow squalls tee off in Ontario as frigid air moves in

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Travel may be extremely hazardous in the snow squalls. Prepare for quickly changing and deteriorating travel conditions. Non-essential travel and outdoor activities should be avoided.

The snow

As the Arctic cold front moved through, frigid air mixed with the warmer Great Lakes to fuel intense snow squalls, which will continue through Thursday afternoon.

The heaviest snow is expected in southern Ontario’s snowbelt communities near Lake Huron and Georgian Bay, as well as the Lake Superior north shore, including Highway 17 between Sault Ste. Marie and Wawa, where 10-25+ cm of snow is possible. Snow squall watches and warnings are in place.

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Snow activity will diminish by Thursday afternoon as shifting winds from another system alter conditions.

The frigid temperatures that follow

Behind the snow, temperatures will plunge to 8°C to 12°C below-seasonal norms, with northern and eastern Ontario seeing the steepest drops.

Timmins could hit an early Thursday low of -23°C, with wind chills dipping into the -30s.

Ottawa is expected to fall to near -20°C, feeling like -27, compared to its seasonal low of -8°C.

Toronto could see the coldest temperature of the season so far

Toronto may see its coldest temperature this season, dipping below -10°C Thursday night with wind chills near -19. Seasonal protection from the Great Lakes will help mitigate extremes in southern Ontario.

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According to the Canadian Red Cross, it is important for everyone enjoying the outdoors to know how to recognize when someone has been exposed to cold for too long, prevent cold-related emergencies, and be able to provide help when needed.

Prevention tips include:

• Cover your head and trunk by wearing a hat and layers of tightly woven fabrics such as wool or synthetics.

• Cover up exposed areas such as your fingers, cheeks, ears, and nose.

• If your clothes get wet when you are in the cold, change into dry clothes as soon as possible.

• Drink plenty of warm fluids to help your body stay warm and hydrated, avoid caffeine and alcohol.

• Eat high calorie food and drinks regularly as the body converts food to energy which heats the body.

• Dress in layers so that you can adjust to changes as you heat up or cool off.

• Bring additional warm clothing when going out for extended periods or in case of emergency.

• Don’t wear tight fitting clothing or footwear that may impair circulation.

• Seek shelter from the wind if you are getting cold, even if it is only behind a tree, hill, embankment, or other landscape feature.

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