Heat warning in effect until Tuesday with rain, storms expected in Toronto

A heat warning in Toronto and much of the province is expected to remain in place until Tuesday, with sweltering temperatures and a risk of strong thunderstorms likely.

Environment Canada issued a heat warning for most of southern Ontario over the weekend. For Monday, temperatures are expected to reach 29 C and feel more like 38 at its peak when humidex values are factored in.

“A humid airmass has reached the region. Daytime maximum temperatures are expected to be near 29 C with humidex values near 40,” Environment Canada wrote in its weather alert for Toronto. “There will be little relief at night as minimum temperatures are expected to be near 20 C.”

Canada’s weather agency says a cooler airmass should arrive by Tuesday, alleviating much of the humidity and hot temperatures.

Toronto could see heavy rain by noon on Monday, accompanied by intense and potentially severe thunderstorms in the afternoon. The storms will pass through almost all of the province, including Hamilton, Ottawa, Barrie, and Bancroft.

Forecasters are monitoring another potential thunderstorm heading into Tuesday across Toronto and southern Ontario. While the hot daytime temperatures will likely have subsided, the risk of thunderstorms will remain for Toronto on Tuesday by 10 or 11 a.m.

The skies will clear by Tuesday afternoon, and we’re expecting a daytime high of 27 C, though it will feel more like 37 with the humidex. On Tuesday evening, there’s another risk of strong thunderstorms developing in Toronto. On Wednesday, conditions will be pleasant, with a forecasted high of 26 C and a mix of sun and clouds.

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