Possibility of large hail and damaging wind gusts
Environment Canada has upgraded the severe thunderstorm watch to a severe thunderstorm warning for northern and southern Niagara.
Residents could see dangerous thunderstorms into the evening, as well as wind gusts around 90 km/hr and hail about the size of a nickel.
Strong wind gusts can cause damage to buildings, strike down trees and blow vehicles off the road.
Some areas could see heavy rain as well.
Environment Canada says severe thunderstorms have the potential to produce tornadoes.
You're advised to take cover immediately if you notice threatening weather.
A special air quality statement also remains in effect for southern and northern Niagara.