An extreme cold warning is in effect for Rainy River district areas, with overnight wind chill values expected to plummet below -40.
Environment Canada issued the advisory for the Fort Frances, Emo, and Rainy River areas, warning that a period of very cold wind chills is forecasted to begin Tuesday night and extend into Wednesday morning.
The agency said cold overnight temperatures are expected to continue through the rest of the week, but are not expected to again drop to below its extreme cold criteria.
Environment Canada said young children, older adults, people with chronic illnesses, and those without proper shelter are among those most vulnerable to the cold.