A special weather statement is in effect for parts of Barrie, Orillia, and Midland, with wind gusts up to 90 km/h expected Wednesday.
The special weather statement will impact Barrie, Collingwood, Hillsdale, Midland, Coldwater, Orr Lake, Orillia, Lagoon City, and Washago.
Environment Canada said winds are expected to be between 70 and 90 km/h, and showers or thunderstorms are possible.
Strong southerly winds will develop ahead of a cold front in the afternoon, the weather agency said.
The weather agency said people should expect the weather to start in Wednesday afternoon and last into the night before ending.
Gusty winds can damage soft shelters, tents and awnings at outdoor events, and loose objects may be tossed by the wind and cause injury or damage, Environment Canada said.
Residents are warned the high winds may result in power outages and fallen tree branches.