It says "a very warm and humid airmass" will settle over eastern Quebec and the Maritime provinces this weekend, and will last into next week. Daytime temperatures will again be near 30 degrees, with humidex values in the mid 30s.
There won't be much relief overnight, either.
Environment Canada has issued a heat warning for the City of Toronto forecasting that "extreme heat event will continue through Thursday", as humidex values are expected to reach 43ºC.More news: Belgium snatches 3-2 win over Japan to set up Brazil clash
A low of 24 C is in the forecast for the early morning hours on Sunday but the temperature will shoot back up to 35 C just in time for Canada Day celebrations.
"Extended periods of heat and humidity like we've seen over the weekend and are expecting over the next few days can be especially challenging for seniors, young children and those with medical conditions that put them at greater risk", said Randy Walker, public health inspector with MLHU.
In response to the extended heat warning, the city has opened a number of cooling centres around Toronto.More news: Archbishop gets 12 months for concealing child abuse
The extreme heat warning has also caused the Toronto Blue Jays to close the roof at Rogers Centre for Saturday's game against the Detroit Tigers as a precaution.
Environment Canada says the high heat and humidity could return on Wednesday. Slowdowns are often required as a safety precaution when the temperature execeeds 30 C. "Given the high temperatures - we had some issues already - I am anticipating that we will likely have a slow order issued across the system".More news: Bridge Collapses At Mumbai’s Andheri Station Due To Incessant Rain, Commuters Stranded
- Asian markets tumble as China-US trade tensions rise
- Scott Pruitt becomes latest Trump official to be harassed at a restaurant
- Sanchez Reveals His Pick For World Cup Golden Boot
- All PlayStation Vue Multi-Channel Plans Will Increase By $5 Starting July 24
- EU Leaders Reach 'Breakthrough' Agreement On Dealing With Migrants
- Hong Kong marks anniversary of return to Chinese rule
- Danny Welbeck says England making most of set-pieces at World Cup
- Facebook’s latest screw-up unblocked people from users’ blocked lists
- Facebook reveals data-sharing partnerships, ties to Chinese firms
- Jesse Lingard full of praise for Gareth Southgate leading England 'revolution'