Depending on where you are in Ontario, Sunday could either be delightful or rather stormy. A cold front trekking in from the Prairies will bring the potential for severe thunderstorms to northwestern sections on the final day of the weekend, along with some of the remaining hotness from the deadly, record-breaking heat wave in Western Canada. Southern sections, however, will enjoy a beautiful Sunday with more tolerable temperatures. The southwest will see some of the heat creep in, though, before it makes its way into the rest of the region for Monday, along with the chance of severe thunderstorms. More on the storm threat on Sunday and Monday, and how long the heat will hang on for, below.
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SUNDAY: GORGEOUS DAY IN SOUTH, POTENTIAL FOR SEVERE WEATHER IN THE NORTH
A cold front is scraping its way into Central Canada, trailing the remaining heat from the record heat last week in the West. Sunday will see the front spark thunderstorms across northwestern Ontario, where temperatures have been in the mid-30s.
An area stretching from Lake of the Woods to Atikokan could see some strong wind gusts with possible severe storms before weakening through the overnight hours over Lake Superior. Other hazards include heavy rainfall and large hail.
Meanwhile, southern sections of the province will see a gorgeous Sunday, with plenty of sunshine and heat surging into the southwest. Temperatures will be in the mid-20s for most of the region, with considerably warmer daytime highs in the extreme southwest corner where Windsor could see values exceeding the 30-degree mark.
MONDAY: STORM RISK SHIFTS SOUTH, HEAT, HUMIDITY RETURN BRIEFLY
Heat will briefly build into the region Monday with temperatures soaring into the upper 20s and into the mid-30s for some. The humidex will also be on the climb, sitting in the upper 30s, even approaching or surpassing 40.
The front will continue to progress east and south through Monday. Morning storms across the Algoma region will give a head start for thunderstorms later in the day for central Ontario, possibly reaching the northern GTA by the evening hours.
The areas at risk of seeing severe thunderstorms will be centred around northern Georgian Bay, including Sudbury, and extending to eastern and southwestern areas. As well, northern sections from Timmins to Moosonee may also see them. The main hazards will be heavy rain, strong wind gusts and small hail.
Thanks to the front's failure to cross southern Ontario on Monday, a second day of humidex values pushing 40 will grace Tuesday. As well, a second area of interest for Tuesday will be from Timmins to James Bay, where strong thunderstorms will try to form around a developing surface low.
LOOK AHEAD: COOLDOWN FOR MID-WEEK, MORE UNSETTLED WEATHER POSSIBLE LATE WEEK
After a cold front swings through Tuesday, temperatures will be considerably cooler for Wednesday and Thursday with highs only in the lower 20s.
Forecasters are also watching a system that is expected to track south of the region late week, but it could be close enough to bring unsettled weather. There is also the chance for temperatures to be even cooler if conditions remain cloudy.
Near seasonal or a few degrees below seasonal are expected as we head into and through next weekend.
Be sure to check for the latest updates on the weather in your area.