Environment Canada is warning residents of southern and eastern Ontario to be prepared for a messy winter storm that is expected to create hazardous driving conditions.

In a special weather statement, the national weather agency said the storm will move into Ontario on Thursday, bringing snow or some freezing rain before changing over to rain.

As the Colorado low persists, the rain should change back to snow Friday or Friday night before ending Saturday, as the cold air of winter arrives, Environment Canada said.

Colder air will cause temperatures to drop below freezing by Friday night.

At this point, it appears the bulk of the snow will stay north of the GTA.

Regions near and north of a line from Wiarton to Muskoka and further east to Brockville are expected to receive more snow than communities further south, Environment Canada said.

Significant snowfall amounts are possible near Bayfield Inlet, north of Parry Sound, to Ottawa.

Snowfall warnings may be issued for those areas.

Flurries and possible snow squalls may add a fresh layer of snow in the southern Ontario snow belts near Lake Huron and Georgian Bay on Saturday.

There is some uncertainty as to the exact path and intensity of the storm, but it has the potential to create tricky driving conditions.

“This weather system has the potential to impact transportation, especially in areas that receive accumulating snow and freezing rain," Environment Canada said.

According to the special weather statement, driving conditions are expected to deteriorate, starting Thursday.

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