Messy, potentially dangerous mix of weather on the way for southern Ontario

Residents of southern Ontario are bracing for a messy, potentially dangerous mix of weather on Thursday and Friday, as another approaching storm system encounters arctic air moving in from over the prairies.

The expected mix of heavy rain, freezing rain and ice pellets across a wide area of the province is likely to cause a commuting nightmare over the next two days across southern Ontario, especially from the shores of southeast Lake Huron to the Greater Toronto Area.

Toronto Pearson Airport is already reporting that some arrivals have been delayed or canceled, but there have been multiple delays and cancellations reported for flights departing for areas currently being affected by these storm systems. The airport authority has issued a Winter Weather travel advisory, and further flight delays and cancellations are likely on Thursday and Friday, before weather conditions improve.

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Heavy rainfall warnings remain in effect for extreme southwestern Ontario, from Windsor and Sarnia, through London and east to Haldimand county, advising that rainfall amounts "in excess of 40 mm" have been received already, and "rainfall amounts of 50 to 80 mm are expected before Friday."

Freezing Rain Warnings have replaced winter storm watches for areas from the southeast shores of Lake Huron, through Kitchener-Waterloo, Hamilton and Niagara, Halton-Peel and the City of Toronto. Environment Canada forecasters are calling for up to 10 mm of freezing rain "with some regions possibly exceeding 20 mm."

Winter Storm Warnings have been called for north of this band of freezing rain — from the Bruce Peninsula, through Barrie, areas north and east of Toronto, through Peterborough and the Kawartha Lakes, Belleville, and out to Kingston. The forecast is for a mix of ice pellets and freezing rain throughout these regions.

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According to the weather warning forecast discussion: "Poor travel conditions are expected over the duration of this event. In particular, the Thursday morning commute may be challenging with icy conditions on untreated roads, especially for areas near and west of the Greater Toronto area to Lake Huron. And it may be even more problematic for the evening rush hour. Of greater concern is the risk of widespread power outages from downed tree limbs and power lines due to significant ice accumulation combined with northeast winds gusting to 60 km/h."

Environment Canada forecasters are also warning that "there is a risk that this could be a major ice storm for an appreciable swath of Southern Ontario."

(Photo courtesy: Ryan Remiorz/Canadian Press)

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