Severe thunderstorms and heavy rain threaten Ontario Wednesday
Cold front to spark widespread thunderstorms across southern Ontario on Wednesday. Heightened flood threat with heavy rain
Widespread thunderstorms, including some severe, are expected across Ontario on Wednesday. Localized flooding presents the most significant hazard as atmospheric moisture levels are forecast between 40-60 mm, highlighting a heightened flood risk.
Gusty winds of 80+ km/h are also possible in organized thunderstorm activity.
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Be sure to stay alert to the changing conditions, and check for any weather warnings in your area.
Severe thunderstorm risk in Ontario Wednesday with localized flooding a top concern
A low pressure system from the Prairies is moving through Ontario, bringing a surge of muggy air across the province. Temperatures will reach the mid-20s, feeling close to 30°C in parts of southern Ontario, including the Greater Toronto Area (GTA).
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Thunderstorms, some severe, are expected Wednesday as moisture and instability peak ahead of a cold front. Rain and storms will develop across cottage country and Muskoka before spreading southward.
Areas near Parry Sound could see 20-30+ mm of rainfall.
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Strong storms are expected along Lake Erie with gusty winds of 80+ km/h possible. Rain will intensify for the GTA during the afternoon and move into Ottawa by evening.
The main concern is localized flooding, as the atmosphere holds 40-60 mm of moisture. Pooling and ponding are risks in areas that receive heavy rain, with over 50 mm possible in the most organized storms.
Residents in the affected areas should monitor weather alerts and be prepared for potential disruptions.
Thunderstorm activity will taper off by Thursday, giving way to a sunny and seasonal start to the weekend.
Stay tuned to The Weather Network for the latest forecast updates in southern Ontario.