Heat warnings are in effect for much of northern Ontario today.
Environment Canada says hot and humid conditions are expected to continue through Friday.
Sault Ste. Marie and the Algoma district is not included in the heat warning as of yet but it is expected to add the Sault and Algoma later today or tomorrow as temperatures are forecast to exceed 30c.
High pressure that is stationary in the area allows for heat to build up during the day.
The weather agency says temperatures could reach a maximum of 29 to 34 degrees Celsius.
It says the conditions can also lead to deteriorating air quality.
It says people should watch for effects of heat illness, such as fainting, heat exhaustion and heat stroke.
To reduce heat risk, the agency suggests scheduling outdoor activities during the coolest parts of the day.
This story was produced with the financial assistance of the Facebook and Canadian Press News Fellowship.
With files from The Canadian Press