It felt like 40 degrees in Toronto on Monday but cooling centres weren't open

The city says it will open its cooling centres as soon as Environment Canada issues a heat warning for Toronto.

The Weather Network says this week could be the hottest one of the year

The City of Toronto is waiting on Environment Canada to declare a heat warning before it opens its cooling centres across the city. (Bruce Reeve/CBC)

Toronto is forecast to feel like 40 degrees today, but the city says its cooling centres won't open until Environment Canada issues a heat warning.

Weather forecasts show a stretch of high heat for Toronto and much of southern Ontario this week. While temperatures will remain in the high 20s and low 30s, humidex values will make it feel like it's in the high-30s on Monday, according to Environment Canada.

It's going to be a hot, humid week and The Weather Network said it's expected to be the hottest week of the summer across southern Ontario and Quebec.

In a statement on Sunday, the city said it doesn't operate its cooling centres until Environment and Climate Change Canada (ECCC) issues a heat warning for Toronto. As of Sunday evening, the agency has not issued a heat warning for the city, but has for the western and eastern edges of the province in Windsor and Ottawa.

"ECCC issues a heat warning when it forecasts two or more consecutive days with daytime maximum temperatures of 31°C or warmer, together with minimum nighttime temperatures of 20°C or warmer, or when there is a forecast of two or more consecutive days with humidex values expected to reach 40 or higher," the city said in the statement.

According to the city, landlords are required to post information on the closest cooling centre on tenant notification boards.

Forecasts don't meet criteria for heat warning, city says

The city's office of emergency management also sent a statement to the CBC about operating hours for its cooling centres.

"Typically, cooling centres run starting on the first day of the heat warning from 11 a.m. to 7 p.m., except Metro Hall which runs 24 hours during heat warnings," it said.

It added that current forecasts don't meet the criteria for a heat warning.

A report from The Weather Network says heat and humidity will build to "uncomfortable and even dangerous levels through the week."