Toronto is struggling through a second consecutive day of extreme heat as students in classrooms without air conditioning look for ways to stay cool, public pools stay open later and trains run slower on overheating tracks.

Temperatures in the city sat around 33 C on Monday afternoon, rising to upwards of 40 C with the humidity factored in.

The extreme heat arrived in  Toronto over the weekend, caused by an expanding large heat dome from the Ohio Valley in the United States heading upwards into Canada.

Sunday saw temperatures above 30 C, with Monday set to be even hotter. The heat wave will last until Wednesday, according to Global News  chief meteorologist Anthony Farnell, and could set records.

Amidst the extreme heat on Sunday, the City of Toronto said it had been forced to intermittently close its public swimming pools because of fears staff would overheat.

On Monday, the city announced it would be keeping pools open until 11:45 p.m. to help people escape the heat, laying on extra lifeguards and medical staff to accommodate the extended hours and avoid closures seen on the previous day.

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Elsewhere, some of the Toronto District School Board’s (TDSB) oldest buildings, still not equipped with air conditioning, stayed open as staff innovated on how to keep students cool.

“Teachers are all opening the windows if that’s going to help with the cooling situation in their classrooms. Sometimes people find if they keep it shut, it’s cooler,” Shari Schwartz-Maltz, TDSB spokesperson, said on Monday morning.

“There’s fans in the school, they’re offering lots of water.”

She said the TDSB was looking to keep schools open, even in the extreme heat, to avoid creating a child care headache for parents. If ordered by the provincial government, however, she said classrooms would close.

The extreme heat also took its toll on Toronto’s travel network.

GO Transit said Monday trains on its commuter routes in and out of Toronto would run five to 10 minutes slower to accommodate the extreme heat.

People are encouraged to stay hydrated by drinking water before they’re thirsty and to watch for early signs of heat exhaustion.

Environment Canada’s seasonal forecast says the summer is expected to be hotter and more humid than normal across Ontario.

— with files from Global News’ Gabby Rodrigues and The Canadian Press

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