Wind chill should play a major role in the temperature plunge expected for southern Alberta overnight.
Environment Canada says an Arctic high pressure system will invade northern Alberta Thursday evening, bringing with it overnight lows near -40 C.
"As this system moves southward this evening winds will pick up to 15 to 20 km/h causing wind chills below -40 C in some areas," said the national weather agency on its website.
"At these extreme wind chill values frostbite on exposed skin may occur in less than 10 minutes."
Wind chill warnings have been issued for:
- Hanna, Coronation and Oyen.
- Lloydminster, Wainwright, Vermilion and Provost.
Southern Alberta could also see some snow in the area.
Environment Canada says flurries could begin near Calgary as temperatures drop overnight. With the wind chill it could feel like -34 C.
There is a 30 per cent chance of flurries on Friday morning in the city, but extreme wind chills are expected later in the day and temperatures could feel like -43 C at night.