Sunday will be particularly hot in a few regions of southern Quebec for which heat warnings have been issued by Environment Canada.
Sunday will be hot and humid in Centre-du-Québec, Montérégie, Laval and the Montreal region.
Humidex values of 40oC or more are expected there in the afternoon.
"The risks are greater for young children, pregnant women, the elderly, people with chronic illnesses and those who work or exercise outdoors," said Environment Canada, which recommends that the population to spend the day in the cool to avoid health problems.
A heat warning is issued by Environment Canada when very hot or humid conditions are expected to present a high risk of illness, such as heat stroke and heat exhaustion.