An extreme cold warning has been issued for Grey Bruce.
Environment Canada says temperatures will rapidly fall through the day Friday, and then wind chill values near -30 are expected to develop overnight.
Forecasters say a reprieve from the extreme cold conditions should arrive Saturday morning.
Environment Canada says extreme cold puts everyone at risk, and frostbite can develop within minutes on exposed skin.
“Watch for cold related symptoms: shortness of breath, chest pain, muscle pain and weakness, numbness and colour change in fingers and toes,” a statement from Environment Canada explains. “Dress warmly. Dress in layers that you can remove if you get too warm. The outer layer should be wind resistant.”