A fast-moving snowstorm sweeping across Ontario has shut down major stretches of northern roads as it advances south toward Toronto.

Lake Superior’s north shore is expected to see about 15 to 25 centimetres of snow, and possibly more in some areas by the time the storm moves through there today.

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Ontario Provincial Police say the storm closed more than 500 kilometres of highway northeast of Thunder Bay.

The Wednesday morning commute could look messy across southern Ontario with about five to 10 centimetres of snow expected tonight and overnight, possible more to the north.

Environment Canada has issued special weather statements including for Sault Ste. Marie, Barrie and the Greater Toronto Area.

Owen Sound and other areas off Lake Huron appear to be bracing for a double dose of winter weather with further snow squalls expected to develop tomorrow.