Toronto heat wave breaks as rain moves in to end scorching week
Posted June 25, 2025 7:37 am.
Last Updated June 25, 2025 1:06 pm.
A multi-day heat event that saw humidex values reach the upper 40s has concluded in Toronto, paving the way for what could be multiple days of rain to cap off a sweltering week.
Environment Canada issued its first significant heat warning of the season on Saturday, June 21, for southern and eastern Ontario and southern and western Quebec.
Maximum temperatures exceeded 30 °C during the day and remained above 20 °C at night. The brunt of the heat was felt on Monday and Tuesday, when humidex values made it feel like 40 to 45 °C. Toronto set a new June 23 temperature record when the mercury hit 36 °C.
The heat warning was officially lifted on Wednesday, but not before eve more heat records were toppled on Tuesday.
Toronto (downtown area) was one of nine parts of Ontario that set daily maximum temperature records on Tuesday, hitting a high of 36.5, which toped the old record of 35.6 set in 1923.
The scorching hot temperatures prompted the Toronto District School Board (TDSB) to issue warnings to parents that conditions inside classrooms would be uncomfortable. Schools across the city remained open during the heat wave.
The good news for many is that the heat and humidity are expected to dissipate, starting on Wednesday and becoming gradually cooler to cap off the week.
Toronto’s daytime high for Wednesday is 29 °C, though it will feel closer to 34. Clouds will increase by the evening hours, with a 30 per cent chance of showers by nightfall, when temperatures are forecast to drop to 19 °C.
An early look at the long-weekend forecast
The rain is expected to stick around for a few days in Toronto, coinciding with a temperature drop on Thursday and Friday. As it stands, the high for Thursday is 22 °C, with humidex values at 26 and a low of 17 °C.
Daytime temperatures will rise to a high of 26 °C on Friday and a low of 19 °C. There is a 60 per cent chance of showers for both days.
Cloud cover is expected to linger in Toronto to open the weekend, though daytime temperatures will rise to a high of 28 °C on Saturday with a 30 per cent chance of showers. Sunday appears more promising, with sunny skies and a forecasted high of 29 °C in Toronto.
Click here to sign up for the CityNews Weather Guarantee and to check out Toronto’s extended forecast.
