'Prolonged heat event' to bake the GTA this week

Bathers swim at Sunnyside Gus Ryder Outdoor Pool, on Toronto’s lakeshore, during a heatwave on July 20, 2022.

It's going to be intensely hot and humid throughout the GTA this week, as a "prolonged heat event" brings sweltering temperatures to much of Ontario.

Environment Canada has issued a heat warning for a vast expanse of the province, from Windsor in the south all the way to Fort Albany in the north, and from Ottawa in the east to Sault Ste Marie in the west.

Daytime highs are expected to hover between 30 C and 35 C, with it feeling more like 40 or 45 with the humidity.

"There will be little relief through the overnight," the federal weather agency says, as temperatures in the low 20s and humidex values between 26 and 30 will persist throughout the early morning hours.

Those who live closer to the shores of Lake Ontario could see slightly cooler temperatures, the warning notes.

"Extreme heat can affect everyone's health," Environment Canada says. "Watch for the effects of heat illness: swelling, rash, cramps, fainting, heat exhaustion, heat stroke and the worsening of some health conditions."

Environment Canada also cautions that hot and humid weather can worsen air quality.

David Phillips, senior climatologist with Environment Canada, says the system baking Ontario this week is part of a heat dome sitting over eastern North America, stretching from Georgia all the way north to Atlantic Canada.

The days will get hotter as the week goes on because the heat dome has a cumulative effect on temperature, he told CBC Toronto on Monday.

"It's like putting the Rogers Centre dome over Toronto and just having all the air sinking and squeezing together, and the sun just baking it. And it just gets hotter and hotter and more uncomfortable and it's hard to find relief," Phillips said.

The city opened 10 wading pools 10 outdoor pools early over the weekend, though the sites will operate on part-time or variable hours until later this month. You can check the city's website for more information.

The wading pools include:

  • Don Russell Memorial Park.

  • Eglinton Park.

  • High Park.

  • Kew Gardens.

  • Knob Hill Park.

  • McCormick Park.

  • Prairie Drive.

  • Rexlington Park.

  • Riverdale Park West.

  • Woburn Park.

The outdoor pools include:

  • Alex Duff Memorial Pool.

  • Heron Park Community Centre.

  • Kiwanis Outdoor Pool.

  • McGregor Park Community Centre.

  • North York Memorial Community Centre.

  • Parkway Forest Outdoor Pool.

  • Pine Point Park Outdoor Pool.

  • Riverdale Park East.

  • Sunnyside Gus Ryder Outdoor Pool.

  • West Mall Outdoor Pool.

If you find yourself in need of an air conditioned space, the city also maintains an interactive map of so-called "cool places," including libraries and community centres, where you can find relief from the heat.