An active, muggy pattern parked over the eastern half of North America won’t spare southern Ontario’s Sunday plans.
The setup looks favourable for a washout on Sunday as the risk grows for very heavy rainfall, with 30-50+mm possible across parts of the region. There could also be severe storms in some locales.
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Sunday downpour and thunderstorm threat
A vast reservoir of rich atmospheric moisture moving toward southern Ontario will send feels-like values close to 40 and fuel a threat for torrential downpours for Sunday.
Instability will build through the afternoon. Combined with the high, atmospheric moisture and a low pressure-system, showers and thunderstorms will be triggered.
The first round will sweep through southwestern Ontario on Sunday afternoon: From Windsor to the Lake Huron shores.
The timing seems to be a little slower than previous models suggested, so the arrival of showers in the Greater Toronto Area (GTA) and Niagara region will likely be late afternoon into the evening.
10-20 mm of rainfall is possible for the Golden Horseshoe, but anywhere from 30-50+ mm of rain will be a possibility beneath embedded thunderstorms.
Some of the storms could reach severe criteria, with strong winds and heavy rainfall as the main threats.
Folks in northeastern Ontario won’t be left out by this pattern, either, as a secondary low moves heavy rain across the region, with embedded thunderstorms, through Monday.
Stay with The Weather Network for all the latest on conditions across Ontario.
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