A heat warning is now in effect for the Kingston, Brockville, and Belleville regions.
Environment Canada is warning that significant heat and humidity will arrive on Friday for most of Ontario, including eastern Ontario.
The weather authority is calling for daytime temperatures to reach the low to mid-30s, with humidex values reaching 40 degrees Celsius or higher.
Minimum nighttime temperatures may only dip to the low to mid-20s.
Environment Canada says these temperatures are supposed to last until Saturday.
The heat is supposed to break on Sunday, when a cooler and less humid air mass is may pass over Ontario, according to Environment Canada.
Communities that could be affected by extreme heat are:
- Charleston Lake
- Quinte West
- Eastern Northumberland County
- Western Northumberland County
- Frontenac Islands
- Sandbanks Park
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“The risks are greater for young children, pregnant women, older adults, people with chronic illnesses and people working or exercising outdoors,” the weather authority said about the heat.
The national weather agency is warning people to never leave people or pets in a parked vehicle in hot weather.
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