Montrealers flocked to parks and ponds in search of relief from the heat. (CBC)Montrealers are being encouraged to find ways to beat the heat as the first real heat wave of the summer is expected to stick around for a while.

Winds in the U.S. Midwest created a hot, humid mass of air that stretched across much of Ontario and Quebec.

A high heat and humidity warning remained in effect for the greater Montreal region on Monday. A smog warning was also in effect.

Those conditions could last for several days in southern Quebec, with the forecast calling for temperatures in the 30s in Montreal until at least Friday.

"This heat wave this week is quite significant," said Environment Canada meteorologist André Cantin. "We'll have almost five days in a row with very warm temperatures and [with the humidity, it will feel like] above 40 degrees, especially during the afternoon."

Montreal's public health agency says infants, the elderly and people with chronic diseases should stay indoors and stay cool.

Drinking water and limiting physical exercise will help minimize the heat's effect, the agency said.

"If someone who is already suffering from a chronic disease and if they live on their own, it is really important … to check on them," said Dr. Norman King, an epidemiologist with Montreal's public health department. "Your neighbours, your parents, your aunts and uncles — just to make sure they know what the preventive measures are."

Some professions are harder hit by the heat than others.

"It's terrible, but we drink a lot of water," said landscaper Mario Lalonde. "We cool off with the hoses and what we can."

At the Royal Victoria Hospital, many of the patients' rooms are not air conditioned, because the hospital's electrical supply is not powerful enough.A landscaper seeks relief from the Montreal heat. (CBC)

In the high-risk pregnancy ward, staff try to accommodate patients with fans and ice water.

"Some families complain," said the ward's head nurse, Francine Martin. "Some families bring in their small air conditioners, except that … we cannot have extra ones on the unit because it affects the whole hospital. It's an old hospital, and the electricity capacity is not optimal."

Despite the heat, Montreal's Jeanne-Mance Park was full of people Monday morning.

Jogger François Auger said he was out early to beat the heat.

"By midday it's going to be too hot, and then I'm just going to go back home … and just stay indoors," he said.

Others meanwhile, took the heat in stride.

"No problem," said Li Hi. "I'm from China. China [is] even hotter than here."