Heat warning in effect for Toronto, humidity will make it feel like 35

Temperatures are expected to hit 30 degrees by the afternoon before cooling off by Tuesday night.

It could feel like 35 today in Toronto as the city and much of the surrounding area remain under a heat warning.

Environment Canada issued the yellow-level alert on Sunday, saying the “first heat event” of the season is expected to last until Tuesday night.

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The warning covers a large part of the GTHA -- including Mississauga, Brampton, Vaughan, Markham, as well as Oakville and Hamilton -- and extends as far west as Windsor.

“Watch for the early signs of heat exhaustion in yourself and others. Signs may include headache, nausea, dizziness, thirst, dark urine and intense fatigue. Stop your activity and drink water,” the federal weather agency warns.

Monday’s forecast is calling for a high of 30 C amid increasing cloudiness and a 60 per cent chance of showers later this evening. There is risk of a thunderstorm later tonight when the low drops to 19 C.

The heat continues on Tuesday, with a high of 30 C (feeling like 34 with the humidity) and a 60 per cent chance of showers, before plunging to a low of 12 C.

Daytime temperatures will pull back by Wednesday, when the high is expected to drop to 16 C and stay below that mark for the rest of the week.

During the heat wave, Environment Canada advises drinking water often, even before you feel thirsty, to replace fluids.

City activates heat relief strategy

To combat the scorching conditions, the City of Toronto says it has activated its “heat relief strategy.”

The city says there are currently more than 380 park water fountains and 247 park washrooms available right now for people to cool off at.

Four additional mobile water trailers will also be available by noon today at Nathan Philips Square, Mel Lastman Square, East York Civic Centre and the Etobicoke Civic Centre.

Cool spaces are located throughout the city for people looking to escape the heat, the locations of which can be found here.