Toronto temperatures are going to swing by 21 C this week

While Toronto is in the midst of a potentially record-breaking heat event this week — with humidex values reaching the mid-40s on Tuesday afternoon — rest assured that cool relief is on the horizon.

Environment Canada has issued a yellow heat warning for Toronto, along with the majority of the province, noting that maximum temperatures could reach 30 to 37 degrees C, which will feel closer to 38 to 45 C when factoring in the humidity.

The hottest July 14 on record in Toronto was back in 1995, when the maximum temperature hit a sweltering 36.8 C.

According to the government department's 7-day forecast, temperatures are expected to remain elevated on Tuesday night, when overnight lows will just barely dip to 25 C, which will feel like 32 C with the humidity.

Toronto's 7-day forecast for the week of July 14 to 20. Photo: Environment Canada.

The heat alert is expected to remain in place throughout Wednesday or Thursday in southern Ontario, when daytime highs will reach 32 C and 31 C, respectively (feeling closer to 37 C and 34 C with the humidity).

On Friday and Saturday, showers will cool things down, bringing daytime highs back down to a more comfortable range in the high-20s. Overnight lows are expected to dip to 18 C on Friday and 17 C on Saturday.

The real relief from the heat wave will come on Sunday, when temperatures are still expected to reach a peak of 27 C, but will drop to a cool and breezy 16 C overnight, representing a temperature swing of 21 C in just a matter of five days.

With already two heat waves recorded in July, you're probably wondering how the rest of the month will play out weather-wise. The Old Farmer's Almanac predicts in its long-range forecast for southern Ontario that July 16 to 25 will bring more scattered thunderstorms to the region, and temperatures will remain cool in southeastern Ontario and warm in the west.

The period from July 26 to 31 is expected to bring even more thunderstorms, along with warm temperatures. Overall, the average temperature in July is anticipated to be 21 C, which is 1 C below average in the east, and 1 C above average in southwestern Ontario.