There is a heat warning in effect for Huron, Perth, Lambton and Middlesex Counties.
The hot temperatures will continue through Wednesday with temperatures reaching the low to mid 30s.
Overnight temperatures will only drop to the low 20s providing little relief from the heat.
Temperatures like this pose risk to everyone but the risks are greater for young children, pregnant women, older adults, people with chronic illnesses and people working or exercising outdoors.
Environment Canada is predicting the arrival of cooler air by Thursday.
Written by Rob Ross
