Environment Canada has issued an Extreme Cold Warning for the Red Lake, Kenora, Dryden, Vermilion Bay, Ignace and Sioux Lookout areas.
Extreme wind chills of minus 40 are expected Monday night into Tuesday morning and Tuesday night into Wednesday morning.
A cold arctic airmass will give frigid temperatures to portions of northwestern Ontario and temperatures will be in the minus thirties along with winds of 5 to 10 kilometres an hour.
You are asked to dress warmly and dress in layers that you can remove if you get too warm.
The outer layer should be wind resistant.
You should also watch for cold related symptoms including shortness of breath, chest pain, muscle pain and weakness, numbness and colour change in fingers and toes.