Summer heat wave set to hit Ontario may bring temperatures not seen in years

Southern Ontario is set to get hit with a strong heat wave just in time for the official start of summer.

Global News meteorologist Anthony Farnell says a large heat ridge or dome will build over the Ohio Valley in the U.S. and expand into southeastern Canada by the end of the weekend.

With the summer solstice, which occurs on Friday and is the longest day of the year for hours of sunlight, residents in southern Ontario will finally start to feel the true heat after a back-and-forth spring season.

Temperatures are expected to soar into the low to mid 30s for at least three days in southern Ontario and two or more days in Quebec, Farnell said.

The hottest day will be on Monday, when the high is forecasted to hit above 35 C in Toronto, and the humidex could briefly reach as high as 45 C.

“This would be a record for the date and the hottest temperatures we’ve experienced in three years,” Farnell said.

But how long will the heat wave stay?

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Farnell says a cool front will slowly slide in from the south on Tuesday into Wednesday bringing an end to the extreme heat, and the chance of thunderstorms.

He also said there is a risk of some “very strong thunderstorms along the warm front as the heat and humidity sweeps in this weekend.”

“Computer models have not been able to show exactly where these storms will form or when but be on the lookout late Saturday into Sunday morning, especially across cottage country and eastern Ontario for quite the light show,” Farnell said.

However, Farnell did note that temperatures will still remain above seasonal up until Canada Day.

“The first heat wave of the year is always more dangerous because our bodies haven’t yet adapted,” Farnell said.

According to Environment Canada, Toronto is expected to see a high of 25 C on Friday for summer solstice, 28 C on Saturday, and temperatures will soar into the 30s for Sunday, Monday and Tuesday.

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