Slowdowns are possible along major highways, including the 400, 404, and 401, due to heavy rain.
Localized rainfall amounts of 30-50 mm are possible under thunderstorms, along with strong gusts and hail up to toonie size.
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By late afternoon and evening, thunderstorms are expected to trigger in southwestern Ontario along the system’s cold front. Large hail, strong winds, and heavy rain will remain the main threats as storms progress.
Humidity persists Friday, but a more seasonal weekend ahead
The humidex will remain in the 30s across parts of Ontario on Friday, though conditions are set to become more seasonal heading into the weekend.
Friday’s forecast includes the chance of pop-up, isolated thunderstorms.
Not all areas will experience storm activity, but localized impacts are possible. There is also a chance of afternoon severe thunderstorms developing in regions north of Lake Erie, including areas near Kitchener and Hamilton.