Alpine weather forecast

Snow-Sun-Sloppy Mix

A taste of winter is in store for the Chic-Chocs Friday thanks to an incoming cold front. Light snow should start around 10am and intensify with the front’s passage around 2pm and then ease to light flurries later this afternoon. Moderate (25-40 km/h) southerly winds ahead of the front will swing around to strong gusty westerlies of 25 gusting 60 km/h in the afternoon. As for temperatures, the high near -1C in the mountains will occur before noon and cold air steadily drops the mercury to reach -14C Friday night. Moisture will be rather limited with this feature, snowfall amounts totaling 4-7 cm with least amounts along the coast and the most for Murdochville.

High pressure will build over James Bay on Saturday which will sustain moderate northwest winds across the ice-free Saint-Lawrence. Temperatures aloft will not be cold enough to generate flurries but the moisture will be sufficient to yield mainly cloudy skies. Sunny breaks will be possible in the afternoon but temperatures will remain below-seasonal with a high of -8C before falling near -15C Saturday night. Sunny skies are expected Sunday morning before high cloud increases ahead of our next system, a major low-pressure system from Colorado that will unfortunately bring a mix bag of precipitation types Sunday night into Monday morning.

So far, models are quite consistent bringing snow and strong southerly winds to the region late Sunday night. The south flow will push mild air over the region causing 5-10 cm of snow to transition to freezing rain near midday Monday and then eventually to 10-15 mm of rain by Monday evening as freezing levels soar to 2500 metres and temperatures approach +4C in the mountains. There is the potential for several hours of freezing rain which would make for very slippery travel conditions Monday afternoon. A rather pronounced drop in the temperatures will eventually follow Tuesday resulting in a new rain crust at all elevations.

Forecast Confidence :

Confidence in the forecaster is generally fair. While most models kept snowfall amounts in the 4-7 cm range with Friday`s cold front, some maintained the post-frontal flurries into Friday night with amounts upwards of 10-12cm. Timing the transition from snow to freezing rain or ice pellets and then to rain will be tricky with Sunday`s storm. Weather alerts for this messy meteorological medley will be likely.