A severe thunderstorm warning has been issued for much of the area, including parts of Durham Region, York Region and Kawartha Lakes.
Wind gusts of up to 90 km/h are expected in some locations.
“Take cover immediately, if threatening weather approaches. Strong wind gusts can toss loose objects, damage weak buildings, break branches off trees and overturn large vehicles. Lightning kills and injures Canadians every year. Remember, when thunder roars, go indoors,” it reads.