Environment Canada issues heat warning with temps expected to hit 35 C next week

Environment Canada has issued a heat warning for Ottawa-Gatineau and eastern Ontario in advance of a "prolonged heat event" that is expected to bring scorching temperatures starting on Monday. 

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The warning says "dangerously hot and humid" conditions are expected for most of the week. Daytime highs on Monday through Thursday are expected to be between 30 and 35 C with humidex values between 40 and 45.

There will be "little relief" in the nighttime hours, as overnight lows are expected to be between 18 and 23 C with humidex values of 26 to 30.

"Watch out for heat related impacts such as heat exhaustion and/or heat stroke. Remember to drink plenty of water," the weather agency says on its website.

The hottest day is expected to be on Tuesday, with highs temperatures expected to reach 34 C in Ottawa. It's also forecasted to be the hottest day of the year so far. 

Environment Canada has also issued heat warnings stretching from Windsor to Ottawa, and northward to Moosonee. A special weather statement for heat has been issued for western and southern Quebec. 

Senior climatologist David Phillips told Newstalk 580 CFRA that while the expected hot and humid conditions are normal in the summer, the first heat wave is the most significant.

"The fact is just people aren’t ready for it yet," he said. "From a health point of view, the first heatwave is often where we see hospitalizations."

Environment Canada has issued a heat warning for eastern and southern Ontario for a "prolonged heat event" starting on Monday. (Environment Canada)

Phillips says the upcoming weather event is significant for its duration.

“It's not a severe weather event that comes and then goes. This has got legs to it. It's a heat dome," he said.

He recommends drinking lots of water and staying away from caffeine or alcohol. Keep an extra eye out for pets and children.

According to Ottawa Public Health (OPH), extreme heat affects children, people with chronic illnesses and the elderly the most. The health authority says extreme heat can cause dehydration, heat exhaustion, heat strokes and sunburns.

Five-day forecast

Environment Canada’s forecast calls for a high of 22 C on Sunday. Tonight will see a low of 15 C with increasing cloudiness near midnight. There is a 40 per cent chance of showers and a risk of thunderstorms.

Monday will see a high of 30 C and a low of 22 C. There is a 40 per cent chance of showers in the morning with a risk of thunderstorm. 

It will be sunny on Tuesday and the temperatures will reach a high of 34 C and a low of 22 C.

A high of 34 C is forecasted for Wednesday and Thursday.

The best hope for relief will come on Friday, when temperatures will dip slightly with a high of 28 C. Saturday calls for a high of 27 C.

With files from CTV News Ottawa's Jack Richardson