Six people died in Montreal over the Canada Day long weekend as an intense heat wave gripped large parts of the country.

Montreal’s extreme temperatures, which peaked at around 35 degrees Celsius on Monday afternoon, were linked to each of the deaths.

Public Health officials said most of the six victims lived alone and were diagnosed with chronic diseases or mental health problems. None of the victims had air conditioning, and they all lived in apartment buildings.

Not included in those numbers was the death of a six-year-old boy who drowned in an apartment pool on Monday. Witnesses say the small pool was at capacity at the time, and there was one lifeguard on duty.

The spate of deaths may seem high, but Dr. Mylene Drouin, Montreal’s regional director of Public Health, says it could have been much deadlier.

“Usually in a normal situation we have 10 deaths per day, so we're not in an excess of mortality,” Drouin said.

Regardless, the City of Montreal has rolled out emergency measures. Firefighters are knocking on doors in neighbourhoods with less greenery where temperatures can rise up to five degrees higher than the forecast high.

Fire crews are expected to knock on about 5,000 doors during the heat wave, and they will offer residents a cooler place to stay.

Montreal’s emergency medical service says it has received an influx of 300 more calls than usual. The agency said it is struggling to meet the demand of people who require transportation to hospital.

According to records, 106 people have died in Montreal due to heat since 2010.

Heat across Canada

Outside Quebec, sweltering heat was felt in four other provinces.

In Toronto and Ottawa, temperatures have remained well above 30 C since Friday. Humidex values this week were expected to reach as high as 43 C in southern Ontario, and Environment Canada issued a heat warning for the densely populated region.

A cooldown isn’t expected until Friday, when a cold front finally passes through.

Heat warnings were also in place for New Brunswick, P.E.I and Nova Scotia, where similarly intense conditions could push the humidex close to 40 on Thursday. Inland communities are hit harder than those along the coast.

The Atlantic heat wave is also expected to break by the weekend.

With files from CTV Montreal