Tornado watches are in place for a large swath of central Ontario from the Bruce Peninsula to Ottawa, as a cold front sweeps into the province with storms that will lift the heat that has blanketed Ontario and Quebec over the past week.
Tornado watches are in effect from the Bruce Penninsula through southern Ontario's cottage country right up to Ottawa, where the capital was briefly under a tornado warning Friday afternoon.
People in the northern Ontario communities of North Bay, Powassan, Mattawa area and West Nipissing-French River were briefly under a tornado warning Friday morning.
Severe thunderstorm warnings remain in effect for much of the southern half of the province including Toronto and Ottawa city.
A watch means conditions are favourable for storms, while warnings mean extreme weather is occurring or imminent.
Severe thunderstorm warnings or watches continue across central and southern Ontario, including Perth, the Halton Hills area, Kingston, London, Peterborough, Kingston, Sarnia and Kitchener-Waterloo.
Montreal also sees the risk for severe weather today with a high of 33 C, feeling like 45 with humidex.
Power outages in Quebec
About 100, 000 customers are without power because of downed tree brances said Louis Olivier Batty, a spokesperson with Hydro Quebec.
The Outaouais and Laurentian areas have been hardest hit by the outages and there will likely be more as the storm tracks towards Montreal, Batty said.
Heavy rain in storms could mean 40 millimetres in southern Ontario and as much as 60 mm in western and southern Quebec, with higher amounts possible in localized areas.
The Toronto area hit day four of a heat wave — considered to be three straight days of 32 C or higher — when a high of 33.2 C was measured at Pearson International Airport Friday. Ottawa reached the same status by Wednesday.
In Mississauga, hundreds of residents of an apartment building were forced outside in the sweltering conditions early Friday after an electrical fire cut power to their building.
The Maritimes will also be muggy and unsettled Friday as humid air moves in with humidex values in the low to mid 30s, and a thunderstorm risk for New Brunswick.
- Read about humidex, the flawed Canadian way to calculate summer discomfort
Eastern Canada isn't alone in facing severe weather. In Western Canada, there is a risk of thunderstorms in large swath south of a line that extends from northeastern B.C. through Saskatoon to southwestern Manitoba.
As of 5:30 p.m. ET, Barrie remained on severe thunderstorm watch.