A large swath of the Greater Toronto Area has been put under a tornado watch as atmospheric conditions prove favourable for "the development of thunderstorms that could produce tornadoes."

Environment Canada issued the severe weather alert shortly before 5 p.m. for Caledon, Halton Hills, Milton, Mississauga, Brampton and a number of cities in three additional regions just west of Toronto.

At 5:48 p.m., the watch was expanded to include the City of Toronto, as well as York and Durham regions. The watch was upgraded to a warning for Dufferin-Innisfil and Halton-Peel at the same time. Residents of these regions are advised to take shelter immediately if threatening weather approaches.

"At 5:44 p.m. EDT, Environment Canada meteorologists are tracking a severe thunderstorm that is possibly producing a tornado. Damaging winds, large hail and locally intense rainfall are also possible," writes the federal weather agency.

"A severe thunderstorm capable of producing a tornado is located 5 kilometres south of Laurel, moving northeast at 55 km/h."

Tornado warnings in red. Tornado watches in yellow. Yes Toronto is in the watch zone pic.twitter.com/zES2Mp6Ndv

— Dave Agar (@dave1agar) August 4, 2020

"Conditions are favourable this afternoon for the development of severe thunderstorms which may produce brief tornadoes," reads Environment Canada's alert for Toronto.

"This is a dangerous and potentially life-threatening situation. Be prepared for severe weather. Take cover immediately, if threatening weather approaches."

This, just one day after four tornadoes were confirmed in central and eastern Ontario following a long-weekend full of wild, beautiful storms.

Environment Canada recommends that, in the event of a tornado, you should do as follows:

"Go indoors to a room on the lowest floor, away from outside walls and windows, such as a basement, bathroom, stairwell or interior closet. Leave mobile homes, vehicles, tents, trailers and other temporary or free-standing shelter, and move to a strong building if you can. As a last resort, lie in a low spot and protect your head from flying debris."