'Drink plenty of water': Ottawa preparing for heatwave starting Monday

A family cools off in the Ottawa River in Ottawa, July 20, 2022. THE CANADIAN PRESS/Sean Kilpatrick

Environment Canada is asking residents in Ottawa to prepare for hot and humid weather conditions starting Monday, as it calls for temperatures reaching above 30 C.

The expected heatwave is expected to last until Saturday, the weather agency says on its website. 

"Watch out for heat related impacts such as heat exhaustion and/or heat stroke. Remember to drink plenty of water," Environment Canada said.

David Phillips, senior climatologist with Environment Canada told 580 CFRA News Talk the humidex will rise to values above 40 during the heatwave, noting that the lows are going to be above 20 C, which ,he says, is concerning.

While the expected hot and humid conditions are normal in the summer, the first heatwave is the most significant, he adds.

"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."

Weather forecast

Monday will see a high of 30 C and a low of 22 C -- 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 -- clear skies at night.

A high of 32 C is forecasted for Wednesday and Thursday. Friday will see a high of 28 C, and Saturday will see a high of 27 C. 

The highest temperature recorded for June 17 was 34.2 C in 1994. The average temperatures for the same day are a high of 24 C and a low of 12.9 C.

A nearly 60-year-old heat record was broken in Ottawa on June 5, as the temperature hit a 31 C high. Environment Canada issued a special weather statement for Ottawa and eastern Ontario, about a "one day heat event". The forecast that day called for a high of 32 C, with the humidity making it feel like 37. The temperature hit 30.9 C at 4 p.m., with the humidex making it feel like 36.

Here’s what to expect and to do during the heatwave:

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

The effects of extreme heat are preventable, says OPH.

"There are many public places residents and visitors can cool off in Ottawa and also ways to cool off at home even if you do not have air conditioning," Ottawa Public Health says on its website.

If you do not have air-conditioning, OPH suggests using a fan. The fan should not be used in a closed room without doors or windows open to the outside.

To find places to cool off in Ottawa during the heatwave, visit the city's website.