A polar air mass is leading to bitterly cold temperatures across parts of North America.
The wind chill is making it feel like minus 50 in Saskatoon and Winnipeg today.
The air mass is also extending into the U.S. Midwest and Great Plains, where some spots could hit minus 35 Celsius, and wind chills could be as low as minus 55.
That's where the Green Bay Packers will host the San Francisco 49ers today in what could become the coldest football game in NFL history.
The cold will stretch into southern Ontario and the U.S. Northeast starting tomorrow.
Environment Canada says the temperature will reach minus 10 Monday afternoon in Toronto. Winds of 40 km/h are expected, gusting to 70 on Monday night.
The temperature will reach a low of minus 21 on Tuesday.