First hot spell of the season coming to southwestern Ontario
Written by The Canadian Press on May 17, 2026
Southwestern Ontario is in for an early taste of summer for the next few days.
Environment and Climate Change Canada says the first hot spell of the season is expected to blanket the region with humidity and temperatures about 10 degrees above normal.
From Windsor, Ont., through the Kitchener-Waterloo region and up to Toronto, the weather agency is forecasting temperatures in the high 20s and low 30s from Monday to Wednesday, with a chance of showers.
Factoring in humidity, Environment Canada meteorologist Kristina Kretchman says temperatures could feel like 35 C in the Hamilton and Toronto areas for the tail end of the long weekend.
Kretchman says the sudden shift to hot weather may feel “dramatic” because of recent below-normal temperatures, but a hot spell at this time of year isn’t particularly unusual.
The weather agency is also monitoring heat in eastern Ontario, around Ottawa, Kingston and the Quebec border, Kretchman says, where temperatures are forecasted up to 29 C.
The meteorologist says a warm air mass from the U.S. is moving up into Ontario, bringing extra heat and moisture.
This report by The Canadian Press was first published May 17, 2026.
Kathryn Mannie, The Canadian Press