Torontonians flocked to beaches and swimming pools, air-conditioned buildings and spots in the shade Wednesday on one of the hottest days in the last decade.

With the city of Toronto under an extreme heat alert, Wednesday’s temperature peaked at 36.3 C at Pearson airport in the afternoon, breaking that weather station’s all-time heat record for July 4. It felt more like 44 with the humidity, according to Environment Canada.

The previous record of 36.1 C was set July 4, 1955.

Wednesday was the third hottest day in Toronto in the last 10 years, and it may be just as warm or even hotter Friday as oven-like conditions persist.

Records were also set Wednesday in Markham, Hamilton, Burlington and several other communities in southern Ontario.

The last time Toronto had a higher temperature in the last decade was July 21, 2011, when the mercury hit 37.9 C, said CP24 meteorologist Chris Potter.

The second hottest day in the last decade was Aug. 1, 2006, as Torontonians roasted in 36.6 C heat.

Extreme heat alert issued by city

The extreme heat alert was issued by Toronto's medical officer of health Wednesday morning in anticipation of temperatures that could feel closer to 40 with humidity.

The temperatures aren’t expected to dissipate anytime soon, either. Environment Canada is predicting a high of 32 C on Thursday and 36 C on Friday before temperatures cool slightly on the weekend with highs of 28 C on Saturday and Sunday.

“During an Extreme Heat Alert, the public is encouraged to call or visit family, friends and neighbours, especially isolated adults and seniors who are at greater risk of suffering from heat-related illness, to make sure they are cool and drinking plenty of fluids,” a news release from the City of Toronto states. “Other groups at risk include people with chronic illnesses, limited mobility and with certain mental health illnesses, infants and young children, people on certain medications and those who are homeless.”

Cooling centres

As part of the extreme heat alert the city has opened cooling centres at the following locations:

  • Metro Hall, 55 John St. (24 hours)
  • East York Civic Centre, 850 Coxwell Ave. (11 a.m. to 7 p.m.)
  • North York Civic Centre, 5100 Yonge St. (11 a.m. to 7 p.m.)
  • Driftwood Community Centre, 4401 Jane St. (11 a.m. to 7 p.m.)
  • Etobicoke Olympium, 590 Rathburn Rd. (11 a.m. to 7 p.m.)
  • McGregor Community Centre, 2231 Lawrence Ave. E. (11 a.m. to 7 p.m.)

The following public pools have also extended their hours until 11:45 p.m.:

  • Alex Duff Outdoor Pool, 779 Crawford St.
  • Alexandra Park, 275 Bathurst St.
  • Giovanni Caboto, 1369 St. Clair Ave.
  • McGregor Park, 2231 Lawrence Ave. E.
  • Monarch Park, 115 Felstead Ave.
  • Smithfield Outdoor Pool, 175 Mount Olive Dr.
  • Sunnyside-Gus Ryder Outdoor Pool, 1755 Lake Shore Blvd.
  • Cummer Park Indoor Pool, 6000 Leslie St.

@ChrisKitching is on Twitter. Don't forget, for instant breaking news, follow @CP24 on Twitter.