The heat wave will finally come to an end on Thursday night but the reprieve from sweltering conditions may be short-lived, according to a senior climatologist with Environment Canada.

Dave Phillips tells CP24 that cooler temperatures should arrive in Toronto for the end of the week, bringing an end to what by that point will have been eight straight days of temperatures of 30 C or more.

The cooldown may not last all that long, though. Phillips says that while the daytime high is expected to top out at 26 C and 25 C on Friday and Saturday, the mercury will shoot back up to the low to mid 30s in time for next week.

“This is not the end, it is not an allotment. People may think ‘Oh my gosh, I should have taken my vacation at this time of the year,’ but no. We are going to see a beautiful weekend coming up with lower humidity but then we will see the temperatures going right back up into the 30s,” he said. “You can maybe turn off your air conditioner and enjoy a few days before the heat builds back up next week.”

Toronto has already had 11 days this year in which the temperature topped 30 C compared to nine such days up until Labour Day of last year.

The Chief Coroner of Ontario told CP24 an investigation is underway into a death possibly caused by the high temperatures. The death took place in eastern Ontario but the exact location has not been revealed by the coroner.

Phillips said that humidex values, some approaching the mid 40s, have made the heat particularly hard to take for many, especially these last few days.

“We have seen about 28 hours where the humidex value has been above 40, and that is very oppressive and sultry, almost jungle-like humidity,” he said. “You often go whole summers without seeing those kinds of conditions.”

Overnight temperatures have hovered around the mid-20s during this heat wave but Phillips said that will change this weekend. He said that while the mercury will remain “elevated,” overnight lows in the mid-teens will provide relief to many. The humidity will also be lower even as the temperature starts to shoot back up, Phillips said.

“It won’t be that sort of tropical kind of humid so it will be much more comfortable,” he said.

Heat affecting GO Transit service

A heat warning issued for Toronto and the GTA remains in effect, with daytime highs of 32 C and 33 C in the forecast for the next two days.

Due to the extreme heat, Metrolinx is continuing to warn GO Transit riders about possible delays. The provincial transit agency says that the delays are a result of slow-orders that are issued amid the risk of rails buckling or warping due to the heat.

“We do slow down our trains proactively to make it safer to travel and that can add a few minutes to your commute. So far it isn’t extreme, the delays, but we do try to prepare our customers ahead of time,” Metrolinx spokesperson Anne Marie Aikins told CP24 on Tuesday afternoon. “The afternoon peak is the worst and we may slow down our trains just to ensure that we can get you where you need to go safely.”

The City of Toronto has also extended the hours at eight outdoor pools to help residents cope with the heart.