Southern Ontario set to bake under another heat wave, humidex to go over 40 C

Southern Ontario is set to sizzle under another heat warning over the weekend, with temperatures hitting the low 40s when humidity is taken into account.

A fresh warning issued by Environment Canada on Friday afternoon predicts temperatures will begin to rise on Saturday and remain high until the middle of next week.

The climate agency said daytime highs will be between 30 and 33C, feeling like 35 to 40 C on the humidex. Overnight lows won’t drop below 19 and 23 C.

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Global News Chief Meteorologist Anthony Farnell said the heat the weather won’t quite reach the suffocating heights felt at the start of summer.

“The heat won’t be as extreme as what we saw in late June or early July, but the duration of this event will make this event memorable and dangerous for some people,” he said.

“Temperatures will remain above 20 degrees at night and during the day they will soar into the low 30s, but the humidex will top 40 for at least the next four days.”

The wildfire smoke, which has hung over Toronto and other parts of southern Ontario for almost the entire week, will also begin to move on as the heat sets in.

“Air quality is starting to improve across southern Ontario and a southerly wind pushes the wildfire smoke back to the north,” Farnell said.

“These same winds will transport in very humid and hot air this weekend and the heat wave will last through at least the first half of next week.”

As part of its warning, Environment Canada reminded people to watch for signs of heat exhaustion such as headaches, nausea, dizziness and thirst.

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