A blast of winter weather is set to sweep across Ontario, delivering snowfall and signs of a white Christmas.

Environment Canada meteorologist Brad Rousseau says a white Christmas looks to be “almost a certainty” for parts of the province where snow accumulates Monday, from around the London area eastward to Quebec.

Up to 20 centimetres is in the forecast across a swath of Ontario from Georgian Bay east toward Perth where the snowfall warnings are in effect.

The Greater Toronto Area is under a winter weather travel advisory and could see between five and 15 centimetres of snow.

The snow is expected to advance on Ottawa this afternoon, becoming heavy at times through the night with accumulations between 10 to 15 centimetres.

As it moves east, the snow is expected to taper off Monday night and into Tuesday.

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