Wintry weather returns to Montreal this weekend

A more wintry weather pattern will evolve this weekend into next week, with several chances for snowfall across the Montreal region. Temperatures will fall back below freezing. While temperatures will not be frigid, the weather will certainly be cold enough for frozen precipitation. (Valley Weather Photo)

December has started off very mild in Montreal Friday morning, with temperatures in the middle single digits. It was 8C (47F) on Ile Perrot this morning, the normal low for December 1 is -7C (19F).

The mild weather will persist today, along with cloud cover and eventually some steady rainfall. Highs will remain nearly steady before falling off this evening. A frontal system over the St. Lawrence Valley will become the dividing line between marginally colder air to the north, and unseasonably warm air to the south.

We have a very difficult forecast this weekend, with several of the computer models offering up very different solutions. Low pressure will move along the aforementioned front this afternoon, with widespread rainfall expected. As the low pressure moves past to our south, slightly cooler air will filter into the Montreal region, with rain changing to a period of wet snow and flurries late this evening. There is also a risk of freezing drizzle, especially in the valley locations.

On Saturday, temperatures will remain very close to the freezing point, with a mix of light snow and rain from north to south. The best chance for a few centimetres of accumulation will occur at the higher elevations north of Montreal and across the Townships. 

On Sunday, a stronger area of low pressure will move along the front, passing very close to Montreal. There is a chance that wet snow will develop in the afternoon, becoming heavy at times and persisting into Monday morning before mixing with rain once again. If precipitation falls as predominately snow, a good 10cm may accumulate in Montreal.

I imagine this forecast will change often as it has in the last 48 hours or so, moving back and forth between rain and snow as the main form of precipitation for Montreal. If you have any travel plans, pay close attention to the weekend forecast. I expect the Monday morning commute will be difficult for many parts of our region.

One thing that seems certain, the weather will turn colder next week, with highs remaining below freezing through Friday.