The Barrie, Orillia and Midland areas are under a severe thunderstorm watch.
Environment Canada issued the watch just after 3 p.m. on Tuesday afternoon, saying conditions are favourable for the development of dangerous thunderstorms, which may be capable of producing damaging wind gusts, large hail and torrential rain.
Officials say thunderstorms are expected to move across Lake Huron from Michigan late Tuesday evening and will continue moving eastward rapidly.
The agency says a few locations could receive several rounds of thunderstorms.
Officials warn that strong wind gusts can damage buildings, down trees and blow large vehicles off the road.
Environment Canada is also reminding residents that heavy downpours can cause flash floods and water pooling on roads, and that lightning is responsible for deaths and injuries to Canadians every year.
“Remember, when thunder roars, go indoors!” the warning reads.
According to the Office of the Fire Marshal and Emergency Management, if threatening weather approaches, residents should take cover immediately.
According to Environment Canada, the thunderstorms are expected to end early Wednesday morning.
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