LIVE UPDATES: Toronto set to sizzle in first heat wave of the summer

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It’s going to be a hot and steamy week in Toronto and much of Ontario as the first heat wave of the summer sets in, starting today.

The Greater Toronto Area and much of the province are currently under heat warnings from Environment Canada.

According to the orange warning issued by the national weather agency for Toronto, temperatures could reach as high as 37 C from Tuesday through Friday, possibly stretching into the weekend as well.

At the same time, minimum temperatures of 21 to 25 C are expected to provide little overnight relief from the sweltering temperatures.

Follow along here for live updates on what you need to know about the heat wave.

Risk of storms almost every day

Because the excessive heat and humidity act as potential energy and fuel for the development of storms, there is the risk almost every day through Saturday of seeing local showers or storms.

This morning, we’ll likely see some active weather on the east side of the GTA. Wednesday could bring some strong storms in the afternoon and evening. Thursday may bring isolated pop-up pm showers.

Friday could see a few showers. And there will remain the risk of a few showers or storms on Saturday. Humidity finally falls for Sunday and Monday. But it will remain very warm. Variable skies for Sunday. Bright sunshine for Monday.

Bill Coulter, CP24 Meteorologist

Canada Day will be one of the hottest days

According to Environment Canada, the peak of the hottest days this week are expected to be Wednesday and Thursday, with maximum temperatures of 34 to 37 C expected. That means those heading out for Canada Day activities will need to be prepared for the sweltering temperatures.

Environment Canada warned that the hot, humid weather can also lead to deteriorating air quality.

“Check on older adults, those living alone and other at-risk people in-person or on the phone multiple times a day,” the weather agency advises. “Watch for the early signs of heat exhaustion in yourself and others. Signs may include headache, nausea, dizziness, thirst, dark urine and intense fatigue.”

People are being advised to avoid strenuous activities outdoors and to drink plenty of water to stay hydrated.

Joshua Freeman, CP24 Journalist

Much of Ontario under advisories

The heat warnings from Environment Canada affect much of the province, stretching from Windsor to Peterborough east West, and into northern Ontario.

Areas under the orange warning include the Greater Toronto Area (GTA), as well as London, Kitchener-Waterloo, Barrie and Collingwood.

A patchwork of yellow warnings are in place around the province as well, including cottage country, Sudbury, sault Ste Marie and Thunder Bay.

Joshua Freeman, CP24 Journalist