What to know
- Toronto, Mississauga and Brampton are all expected to experience hot and humid conditions Tuesday, with temperatures near 30 C and humidex values ranging from 33 to 35.
- Forecasters are warning of possible severe thunderstorms, gusty winds and a sharp cooldown later Tuesday evening across parts of the GTA.
- Residents are being urged to stay hydrated, avoid prolonged outdoor exposure during peak heat and monitor weather alerts throughout the day.
Toronto is in for a hot and stormy Tuesday as temperatures are expected to hover near 29 C, making it feel like 35 C due to humidity.
Strong thunderstorms are also likely later in the afternoon going into the evening, backed with gusty winds followed by a sharp cooldown overnight.
The heat warning for Toronto and other parts of the Greater Toronto Area remains in effect, with authorities urging residents to stay hydrated and limit the outdoors during peak afternoon heat as humid conditions take a hold of the city and the GTA.
Brampton weather forecast for today
Brampton residents can expect the temperatures to near 30 C and humidex values around 33 before likely thunderstorms and winds begin to move in Tuesday evening.
Mississauga weather forecast for today
Weather conditions in Mississauga will mirror Toronto and other key parts of the GTA, such as Brampton, with temperatures likely touching 30 C and feeling close to 34 C.
Forecasters are expecting hot and humid weather across Mississauga with possible thunderstorms and windy conditions kicking in later in the day.
Toronto heat warning remains in effect
Environment and Climate Change Canada (ECCC) issued the city’s first heat warning of the year beginning Monday, May 18 and lasting into Tuesday night. The temperatures were forecast to hit around 30℃ and feel closer to 36 with humidity.
The overnight lows ranged between 18℃ and 20℃, meaning there won’t be much relief once the sun goes down either.
The City of Toronto said it is responding to the season’s first heat warning by activating its Relief Strategy which includes expanding drinking water access by providing additional mobile water trailers that will be made available by noon on Monday at:
- Nathan Philips Square
- Mel Lastman Square
- East York Civic Centre
- Etobicoke Civic Centre
The trailers will remain onsite until the heat warning is lifted, with the exception of Nathan Philips Square, which will remain in place throughout the FIFA World Cup 2026.
