Extreme heat wave in Ontario leaves vulnerable people at risk

TORONTO – As much of Ontario sweltered through Canada Day, advocates warned that vulnerable populations are at the greatest risk from the extreme heat.

Orange heat warnings blanketed Environment Canada’s weather map, stretching from Windsor to Toronto to Ottawa.

Temperatures reached into the mid-30s in those areas. 

There were also heat warnings in place for northern Ontario, where places like Sault Ste. Marie, Timmins and Thunder Bay saw temperatures in the 30s, with humidex values near 40.

Keith Hambly, CEO of Fred Victor, a Toronto-based organization that provides shelter, housing, and support services across the city, said it was important for all community members to support one another.

Fred Victor has a “Keep Cool” outreach team that helps unhoused residents during heat waves. The team deploys whenever the city issues a heat warning, checking on people at known hot spots across the city, including parks and areas near shelters, and distributing water and sunscreen. They can also point people toward free cooling spaces run by the city and other agencies.

Hambly said some other populations are at an increased risk during heat waves, such as the elderly or individuals who live alone and have minimal connections outside of their own space.

“It’s important that anybody in the city of Toronto be a good neighbour and check in on people,” he said.

Heat can be especially dangerous for those who are chronically homeless, Hambly said, since many already face what he called “premature aging,” meaning health conditions more typical of someone decades older, including diabetes and heart issues.

He added that people on medication faced extra risks, since many prescriptions are meant to be taken in a temperature-controlled setting. “If you’re constantly outside taking those medications, it can impact people very severely,” he said.

The recent closure of supervised consumption sites in Ontario also means that people who once used drugs under supervision are now doing so on the street.

Combined with an increasingly toxic drug supply, Hambly said it is unclear how extreme heat affects people using drugs outdoors.

“We don’t know what the impact of excessive and exposed heat could be on the body,” he said.

Environment Canada said the hot and humid conditions across the province could last through the weekend.

Health experts said anyone spending time outdoors should limit alcohol consumption, as it increased dehydration and raised the risk of heat-related illness such as heatstroke.

This report by The Canadian Press was first published July 1, 2026.