Montrealers try to escape the heat at the beach in Jean-Drapeau Park. (CBC) Officials in regions across Quebec announced measures to help residents cope with the scorching heat as the first heat wave of the season entered its third day.

A high-heat-and-humidity warning remained in effect for much of the south of the province as temperatures remained in the mid-30s on Wednesday.

Extreme heat measures are launched following three consecutive days on which the average temperature reaches 33 C and the nighttime temperature does not drop below 20 C.

In Montreal, where temperatures reached 33.5 C on Wednesday, breaking the previous record of 33.2 C set in 1982, officials said they were prepared for the situation.

The city designated 108 public areas as cooling-off centres and extended the opening hours of public swimming pools and made them free of charge for the duration of the heat wave.

Community health clinics, or CLSCs, will be working to identify and contact potentially vulnerable seniors living alone while police and firefighters will be going door to door in at-risk areas to let people know what services are available, officials said.

Hospital staff will be performing regular checks on patients while seniors living in long-term care centres will be required to stay in air-conditioned areas for two to three hours a day.

The director of Montreal's public health agency, David Levine, said he was hopeful officials would be able to prevent heat-related deaths.

"Our public health studies have shown … there often is around 100 additional deaths during a period of heat wave than we would find during a non-heat wave period of time," said Levine. "That is why these measure are being put into place.

"The main message is for the population to be vigilant, not only for themselves but for their neighbours, members of their family, young children, the elderly person who lives next door, [or on the] third floor, doesn't get out very much.

"[If you] haven't heard from them lately, give them a knock on their door — make sure they're OK."

In the Montérégie region, Quebec City and Saguenay, some areas have also extended pool hours to help people cool off.

In the Eastern Townships, cooling centres are being opened in Sherbrooke, Magog and Asbestos.The director of Montreal's public health agency, David Levine, says officials are prepared to help people cool off. (CBC)

Citizens in other areas are being encouraged to visit air conditioned spaces such as libraries and shopping centres in order to avoid heat stroke.

Meanwhile on Wednesday, Montrealers were doing their best to beat the heat, each in their own way.

"If it's 25 outside, then it's hotter in the bakery," said Fairmount Bagels owner Irwin Shlafman. "If it's 35 outside, then it's hotter in the bakery.

"We just all come in and drink lots of water. You know, deal with it."

Nearly 1,000 children from various day camps tried to keep cool on the beach at Jean-Drapeau Park.

The high heat levels had many parents concerned, said Kateri Oesterreich of the Our Gang Kahnawake Day Camp.

"We were contemplating not coming, in fear of them getting sunburn or heat stroke, but it turned out the weather is not to the extreme that we anticipated," she said. "And, the cold water at this beach is absolutely perfect."