Phones across northern Durham Region lit up on Thursday afternoon, as an emergency alert warned of severe thunderstorms and possible tornados.
Environment Canada says a cold front is expected to sweep across Southern Ontario, bringing scattered thunderstorms to the area.
Some of these storms could produce heavy rain, damaging winds and large hail.
Winds could be up to 110 kilometers per hour and nickel-sized hail could fall in some areas.
The weather agency is asking everyone to take the proper precautions.
They say you should secure loose items outside or near your home, move things that could be damaged by wind or hail and take steps to prevent flooding on your property.
If you’re outside when thunder roars, head indoors right away.
Drivers should watch out for flooding on roads, downed power lines and tree branches, among other hazards.
Photo courtesy of Environment Canada