Hottest June 1 in Ottawa history

Ottawa set a new temperature record before 12 p.m. on the first day of June and the temperature kept warming up through the afternoon, as a multi-day heat event grips the capital.

Environment Canada has issued a heat warning for Ottawa and Prescott-Russell, calling for daytime temperatures of 33 C on Thursday and Friday.

The temperature hit 29.8 C at the Ottawa International Airport at 11 a.m. Thursday, setting a record for the warmest June 1 in Ottawa’s history. The old record was 29.6 C, set back in 2011. According to Environment Canada, the temperature warmed up to 35.1 C Thursday afternoon.

Relief from the heat will arrive this weekend.

"Overnight temperatures are expected to be in the high teens, providing little relief from the heat. Cooler temperatures return on Saturday," the weather agency said in a statement. 

"Hot and humid air can also bring deteriorating air quality and can result in the Air Quality Health Index approaching the high risk category.

"Extreme heat affects everyone. The risks are greater for young children, pregnant women, older adults, people with chronic illnesses and people working or exercising outdoors."

Friday's forecast high of 33 C would also break the record for the hottest June 2 in Ottawa’s history. The current record for June 2 is 30.4 C, set back in 2014.

Ottawa Public Health warns early season heat waves can be dangerous.

"Remember: early heat waves can be especially dangerous since it takes our bodies up to 2 weeks to adjust to hot weather," OPH said on Twitter. "Take it easy until your body has adjusted by drinking more water & taking extra precautions."

Here is a look at the forecast for Ottawa.

Expect sunny skies on Thursday and a high of 33 C. The humidex will make it feel more like 35.

It will be partly cloudy this evening with a 30 per cent chance of showers and a risk of a thunderstorm. The overnight low will be 19 C.

Friday will see a mix of sun and cloud, with a 60 per cent chance of showers in the afternoon. There will also be a risk of a thunderstorm. High 33 C, with the humidex making it feel like 37 degrees. 

It will be cloudy Friday evening with a 40 per cent chance of showers. The overnight low will be 14 C.

The outlook for the weekend calls for a mix of sun and cloud and a high of 23 C on Saturday. Sunday will see a mix of sun and cloud, with a high of 25 C.

The normal temperatures for this time of year are a high of 22 C and a low of 11 C.