Toronto is currently facing a yellow-level severe thunderstorm warning, alongside other regions in the Greater Toronto Area (GTA). Weather forecasters are closely monitoring a rapidly evolving weather system that is anticipated to bring several rounds of severe storms, heavy rainfall, strong winds, large hail, and the potential for isolated tornadoes throughout the day.
Environment and Climate Change Canada (ECCC) expanded their warning area early this morning as severe thunderstorms advanced eastward across southern Ontario. Toronto, Pickering-Oshawa-Southern Durham, and Vaughan-Richmond Hill-Markham are among the areas under alert. Reports of heavy rain, low visibility, and hail have already emerged from communities north and east of the city.
The weather advisory from Environment Canada for Toronto highlights the risks, stating that heavy rain could lead to flash flooding and significantly reduce visibility, while large hail poses a threat of damage and injury.
While a previous fog advisory for Toronto has ended, some regions in the GTA are still under a yellow-level fog warning. The current weather system follows a humid day in Toronto, with humidex values peaking near 40.
Severe thunderstorms have already begun moving eastward on Wednesday, with strong wind gusts, quarter-sized hail, and heavy rain affecting areas including Markham, Pickering, Ajax, Whitby, Oshawa, Newmarket, and Lindsay.
The morning commute is expected to be foggy, slow, and hazardous, with visibility dropping in some areas and the possibility of 30-50 mm of rain within an hour.
The Toronto and Region Conservation Authority (TRCA) has cautioned that watersheds are saturated after Tuesday’s rainfall, increasing the risk of flash flooding and dangerous river conditions with additional heavy downpours.
The forecast indicates that the most severe weather conditions will intensify from the afternoon into the evening as a second wave of thunderstorms moves through the GTA. This round is predicted to have significant impacts, including tree damage, power outages, property damage, and hazardous road conditions. Residents are advised to seek shelter promptly if storms approach.
Southern Ontario continues to experience warm, moisture-laden air, with temperatures expected to reach a high of 27°C and a humidex of 35. Coupled with an incoming low-pressure system from the U.S. Midwest, the conditions are conducive to multiple rounds of severe thunderstorms.
Weather conditions are set to improve on Thursday with mostly cloudy skies and a chance of showers, followed by a calmer period from Friday to Sunday as temperatures return to seasonal averages.
