August and meteorological summer may be coming to a close, but the warm weather isn’t ready to depart southern Ontario just yet.
In fact, warmer-than-normal temperatures will be widespread from the Prairies to the Great Lakes, stretching into western Quebec, during the first week of September.
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Midsummer heat and humidity will be present in southern Ontario this week, with a crack at hitting the 30-degree mark for many locales. But the warmth will come with multiple chances of rain and thunderstorms.
Chance for midsummer warmth and storms this week
Atmospheric moisture from the Gulf of Mexico builds in southern Ontario this week.
Monday, Tuesday and Wednesday will bring a mix of sun and cloudy periods with a few rounds of rain and thunderstorms as southern Ontario will be in the ring of fire, with very hot and humid conditions over the U.S. Midwest.
That will bring a return of the high humidity we’ve felt on several occasions this summer. Places like Windsor and London could see temperatures begin to climb on Monday.
On Tuesday, Windsor has a forecast of 34 C with a feels-like value of 43 while Ottawa has a forecast of just 20 C. Heat-related illnesses could become widespread in the southwest and heat alerts may be issued.
The humidity will peak on Tuesday into Wednesday, with thunderstorm energy building–raising the threat for widespread, multi-day storm chances. Some of the storms could reach severe criteria.
With plenty of atmospheric moisture to work with, heavy rainfall and localized flooding will be possible hazards.
Beyond, cooler weather is expected late next week, hovering around seasonal, but temperatures should trend warmer during the long weekend. Warmer-than-normal weather conditions are expected to dominate during the second week of September for back to school, and the following week.
Stay tuned to The Weather Network for the latest forecast updates for Ontario.