Large hail and tornado risk: Severe weather risk for NW Ontario tonight
A low pressure system moving into northwestern Ontario Friday evening brings a risk of severe storms, including heavy rain, strong winds, and hail, followed by a significant temperature drop once it passes.
A low pressure system moving out of South Dakota is set to bring active weather to northwestern Ontario late Friday and into Saturday.
Thunderstorms are expected to develop Friday evening along a warm front, intensifying south of the border before crossing into northwestern Ontario. The storm setup and atmospheric conditions could support the development of tornadoes, particularly near the international border.
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Be sure to stay alert to the changing conditions, and check for any weather warnings in your area.
Risk for strong storms and a slight tornado threat Friday evening
These storms will initially form as isolated cells over Wisconsin, but will likely take on a linear structure as they approach the Canadian border.
The main risks include large hail (up to 4 cm in diameter), intense rainfall, and damaging winds. There is also a chance for brief tornadoes near the international border due to a Quasi-Linear Convective System (QLCS) setup.
Localized flooding is possible in areas experiencing heavy downpours.
Thunder Bay may see storms between late evening and overnight hours. While the proximity to Lake Superior could reduce the chances of severe weather, heavy rain remains likely.
Poor confidence in model timing adds uncertainty to the storm's exact impacts, with later development potentially reducing its severity.
Once the cold front sweeps through, a cooler northwesterly flow will bring below-seasonal temperatures to the region for several days.
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Kenora, for instance, will experience highs below 15°C, a stark contrast from recent weeks.
Stay weather-aware as conditions evolve.