Extreme cold, wind chill near -40 C and snow squalls off Georgian Bay

A blast of Arctic air is settling over much of northern Ontario on Thursday morning with extreme cold weather bringing temperatures near -40 C with the wind chill as snow squalls continue of Georgian Bay.

Environment Canada weather alert map at 8:15 a.m. on Jan.18.24 (Red- extreme cold or snow squall warning, grey - winter weather travel advisory)

Environment Canada's extreme cold warning is in effect for Smooth Rock Falls and communities west to the Manitoba border.

The temperatures will rise during the day, but the extreme cold could return Thursday evening.

In the Far North of Peawanuck and Fort Severn, an extreme cold warning is also in effect where the wind-chill will drop temperatures to near -45 C.

"Cover up. Frostbite can develop within minutes on exposed skin, especially with wind chill," the weather alert said.

"Watch for cold-related symptoms: shortness of breath, chest pain, muscle pain and weakness, numbness and colour change in fingers and toes."

SNOW SQUALL WARNINGS

Meanwhile, snow squalls continue east of Georgian Bay due to lake-effect snow – including Parry Sound to Port Severn and Burk's Falls to past Gravenhurst.

The snow squalls will continue into Thursday afternoon "before weakening and shifting south of the region" by early in the evening.

"Snow squalls cause weather conditions to vary considerably; changes from clear skies to heavy snow within just a few kilometres are common," Environment Canada said.

"Travel is expected to be hazardous due to reduced visibility. Road closures are possible."

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Between 10 and 20 cm of more snow is expected with peak snowfall rates of more than five cm/h possible Thursday morning.

"If you must travel, keep others informed of your schedule and destination and carry an emergency kit and mobile phone," the weather alert said.

Lake effect snow will also impact visibility from Port Severn to Barrie where five to 10 cm of more snow is expected.