Environment Canada has issued a heat warning with temperatures reaching 32 C for the next few days.
The weather agency said a hot and humid airmass arrived in the region Saturday. Daytime maximum temperatures are expected to be 31 C to 33 C with humidex values near 40 C.
There will be little relief as the sun goes down with temperatures expected to be near 22 C.
Hot and humid air can also cause poor air quality.
It's recommended people limit sun exposure and drink plenty of water.
A cooler airmass is expected to arrive by Tuesday.