hi-heat-quiz-852-8col

(CP) ((Canadian Press) )

Toronto likes to think of itself as the hottest spot in the country but on Thursday that title became official.

With the temperature reaching 37 C and the humidex making it feel like 51 C — Canada's largest city became Canada's hottest city, at least for one day.

Even before the sun came up Toronto had already set one record: the hottest night ever recorded in the city.

The overnight low was a sweltering 26.6 C.  Before that the record was 26.3, set in August 2006.

Toronto cooling centres

Metro Hall Cooling Centre, 55 John Street at King Street West.

Centennial Park Recreation Centre, 1967 Ellesmere Road, west of Dolly Varden Boulevard.

Driftwood Community Centre, 4401 Jane Street, north of Finch Avenue.

East York Civic Centre, 850 Coxwell Avenue, south of O'Connor Drive.

Etobicoke Olympium, 590 Rathburn Road at Melbert Road.

McGregor Community Centre, 2231 Lawrence Avenue East, east of Birchmount Road.

North York Civic Centre, 5100 Yonge Street, north of Sheppard Avenue West.

Environment Canada put out a weather warning because of the extreme heat and humidity, warning people that "during times of high heat and humidity, it is critical to stay properly hydrated by drinking plenty of fluid like water or juice." 

Senior climatologist Dave Phillips said the heat and humidity is stuck over southern Ontario and moving very slowly.

"It's very sluggish.  It just doesn't move.  It's like a sumo wrestler.  It just kind of stands it's ground and nothing can push it out of the way," Phillips told CBC News.

Peter McIntyre with Toronto Emergency Services said calls were up by about 10 per cent on Thursday.  

Paramedics were sent to homes, apartments and workplaces to deal with heat-related emergencies.

Most of the problems, McIntyre said, involved "difficulty breathing, chest pain, diabetic problems and just sort of general malaise." 

Patricia Anderson, who is in charge of the city's cooling centres, says they've seen a steady stream of customers — almost 700 people had come to the centres by midday.

"People come in, they get a glass of water and just have a little rest," she said.

Rogers Centre roof closed

The blistering temperatures even forced the Toronto Blue Jays to do something they've never done before.

"This I believe is the first time in the history of the Rogers Centre we've had to close the roof because of heat," said Stephen Brooks, the Jays' vice president of operations.

Brooks says the team  gave out free bottles of water and cranked up the air conditioning during their afternoon match with the Seattle Mariners.

Most surprisingly, although Toronto did set a record for the hottest July 21st, it didn't quite manage to hit the all-time mark.

Although the temperature peaked at a sultry 37.1 C on Thursday, that's still below the record of 38.3 C set back in August 1948.

Temperatures will start to fall over the next few days, but the daytime highs will remain above 30 C until Sunday. 

"Our [seven-day] forecast has every day at or above the seasonal mark," said CBC meteorologist Nick Czernkovich.