A heat advisory has been issued by the chief public health officer for southwestern Manitoba, including Winnipeg, as very high humidex levels of up to 40 could be reached in the next three-four days.
There is the possibility that higher humidex levels could occur along the U.S. border near Melita.
Manitobans are advised to take precautions by drinking plenty of water, limiting excessive physical activity, wearing a hat and taking care to protect children, the elderly and pets from the heat.
The humidex, short for humidity index, represents the real-feel temperature when the heat and humidity are combined.
Humidex levels of 37 to 39 may occur in the areas around Melita, Virden, Brandon, Dauphin and Swan River today. Over the weekend, humidex levels could approach 40 from the Saskatchewan border through to Morden, Winkler, Emerson and Sprague including Winnipeg.
There is a possibility of an extended period of very high humidex levels (40 and higher) along the U.S. border near Melita, while high humidex levels (37 to 39) are forecast through to Monday in the areas including Brandon, the south Interlake, the Whiteshell bordering on Nopiming Provincial Park, and Winnipeg.
People are reminded to take breaks from the heat whenever possible as "exposure to heat for too long a period can lead to dehydration, heat exhaustion, heat stroke, worsening of other health conditions or, rarely, death. Symptoms of prolonged heat exposure include headache, nausea, weakness, dizziness, fainting, confusion, rapid breathing and dehydration," the warning said.
It said health risks related to heat exist for everyone but are higher for older adults, young children, people on certain medications, people with chronic health conditions and people living alone. The effects of heat can build up over a few days if the temperature and humidity continue.