Second heat event to hit Toronto, southern Ontario starting Monday

FILE - People enjoy the weather by the waterfront on a hot day at Sugar Beach park in Toronto, on Sunday, May 17, 2026. THE CANADIAN PRESS/Sammy Kogan

Toronto will bake under another heat event this week with daytime highs in the mid-30s and humidex values as high as 45.

As a result, Environment Canada has issued a yellow heat warning for the city and the rest of southern Ontario.

• Your hourly and 7-day forecast on our CP24.com weather hub

The heat event is set to begin on Monday and will last until either Wednesday or Thursday evening, Environment Canada said.

“Tuesday will mark the peak of this heat event. Maximum temperatures are expected to reach near 36 C in some areas,” the national weather agency noted in its advisory.

During the heat event, Ontario residents could see humidex values of 38 to 45.

There will be little relief from the heat, as temperatures won’t dip to lows below 20 C for the duration of the heat wave.

“Hot and humid air can also bring deteriorating air quality and can result in the Air Quality Health Index approaching the high-risk category,” Environment Canada said.

“Take action to protect yourself and others – extreme heat can affect everyone’s health. Determine if you or others around you are at greater risk of heat illness. Check on older adults, those living alone and other at-risk people in-person or on the phone multiple times a day.”

Signs of heat stroke include red and hot skin, dizziness, nausea, confusion and change in consciousness.

“Plan and schedule outdoor activities during the coolest parts of the day. Limit direct exposure to the sun and heat. Wear lightweight, light-coloured, loose-fitting clothing and a wide-brimmed hat,” Environment Canada said.

During the first heat wave of the summer two weeks ago, Toronto Public Health said hospitals reported a total of 39 heat-related ER visits.

Toronto activates heat relief strategy

With a heat warning in effect, the city says its heat relief strategy has been activated.

Four mobile water trailers offering water fountains and bottle-filling stations will be available at Nathan Phillips Square, Mel Lastman Square, East York Civic Centre, and Barbara Hall Park starting on Monday.

They will remain on-site until the heat warning ends.

The city says it also has more than 500 cool spaces where residents can get some relief from the heat. They include Scarborough, Etobicoke, York, East York, North York Civic Centres and Metro Hall, all of which will operate on extended hours.

More than 170 splash pads will operate daily from 9 a.m. to 9 p.m.

The city says residents can also cool off at its 57 outdoor pools, eight of which will operate on extended hours during the heat warning. They are:

• Alex Duff Pool, 779 Crawford St. 
• Giovanni Caboto Pool, 1367 St. Clair Ave. W. 
• Heron Park Pool, 292 Manse Rd. 
• McGregor Park Pool, 2231 Lawrence Ave. E. 
• Monarch Park Pool, 115 Felstead Ave. 
• North Toronto Memorial, 200 Eglinton Ave. 
• Smithfield Park Pool, 175 Mount Olive Dr. 
• Sunnyside Gus Ryder Pool, 1755 Lake Shore Blvd W. 

With files from The Canadian Press