Another shot of arctic air but milder weather for Christmas

Plowing operations in Lasalle on Saturday, after a quick 5 to 10cm of snow fell across southern Quebec. The cold temperatures made roads extremely slick. (ValleyWX)

Low pressure is moving along the St Lawrence River this morning, with a trailing cold front charging across Ontario. Between 5 and 10cm of snow fell Saturday, followed by a prolonged period of mainly freezing drizzle here in Montreal. The heavier precipitation has remained south of the international border. That being said, we have a glaze on everything this morning in southern Quebec, including roads and sidewalks. The power grid seems to be ok so far, with a little more than 1300 customers without electricity according to Hydro Quebec.

The current temperature in Montreal remains chilly, as I expected it would be. Cold air is very difficult to dislodge form the St. Lawrence Valley. The high today will reach -4C (25F) this morning, before the cold front arrives. Temperatures will rapidly fall afterwards, reaching -21C (-6F) by Monday morning. Gusty northwest winds will develop as well, up to 50km/h, producing wind chill values close to -30C (-22F). The freezing drizzle currently falling in Montreal, will change over to light snow and end by 1pm. Skies will slowly clear out this afternoon. Monday will be sunny and cold, with a high temperature of -14C (7F). Milder weather is expected leading up to Christmas Day, but with a chance of more snow by Thursday.