Sweltering heat wave rolls through Ontario, Quebec and Atlantic provinces

It felt like 45 C in parts of Canada on Wednesday as a punishing heat wave continued to roll across Ontario, Quebec and the Atlantic provinces.

Authorities are warning residents to take precautions and offering extra services to soften the impact of soaring temperatures that are expected to last until Friday.

New studies have illustrated the deadly toll of extreme heat in Canadian cities, especially Toronto and Montreal, where hundreds have died in recent years because of high temperatures.

Environment Canada says daytime highs are expected to hit 30 C to 35 C, with the humidex making it feel closer to 45 C in some areas. Overnight temperatures are expected to stay above 20 C until Friday night.

Toronto and Ottawa have both extended hours at certain outdoor pools until Thursday. In Montreal, public buildings, including libraries and cultural centres, are also open longer than usual to provide escape from the heat. The city has also opened many outdoor swimming pools early in response to the heat wave.

Quebec’s Health Department is recommending people spend at least two hours a day in an air-conditioned space, take at least one cool shower or bath a day, and limit physical activity.

Environment Canada is also reminding people to check on loved ones, especially those who are disabled, mentally ill or living alone.

Such a severe heat wave is rare this early in June, the agency said in a briefing for reporters on Wednesday. The heat wave has already broken some temperature records, and could break more. In Montreal, for example, the highest recorded June temperature is 35 C, a record set in 1964. On Wednesday, the city was expected to reach 34 C.

A retirement home in a Montreal suburb was without power for air conditioning on Wednesday morning because of scheduled maintenance by the provincial utility, a situation that caused “anxiety” among staff and residents.

Hydro-Québec spokesperson Jonathan Laporte said the network maintenance in Pointe-Claire, Que., could not be postponed without risking longer-term outages. That left 1,600 clients without power from about 7 a.m. to just after 1 p.m. Wednesday.

Mr. Laporte said the utility contacted Chartwell Le Wellesley, the retirement home, on Monday to co-ordinate the planned outage. Hydro-Québec delivered a generator to the home Wednesday morning to use in case the outage lasted longer than expected and mobilized extra staff to ensure the work happened faster, Mr. Laporte added.

A new study from Quebec’s national research centre shows that high temperatures in Quebec are associated with 470 deaths, 225 hospitalizations and 36,000 emergency-room visits each summer. “I think that this really provides a solid argument to say that we need to put measures in place to reduce this burden, which is going to be greater and greater,” said the study’s main author, Jérémie Boudreault, with Institut national de la recherche scientifique.

A new Statistics Canada report, meanwhile, concludes that extreme heat events caused 700 excess deaths in the country’s biggest cities in the first two decades of this century. The toll was steepest in Toronto and Montreal, possibly because they have more renters who may not have air conditioning.

With reports from Kelly Grant and The Canadian Press