Two batches of snow followed by the coolest temperatures of the winter are in store for Southern Manitoba over the next few days.
An Alberta Clipper will begin it’s march across the Prairies today, rapidly moving from Northern Alberta east-southeast into Northern Minnesota by tonight. This system will drag a warm front eastwards across Southern Manitoba, spreading 1–2cm of light snow across the Red River Valley. The snow will ease off this afternoon to just scattered light flurries as the weak leading impulse moves off into NW Ontario.
Temperatures will warm to around –8°C by this afternoon, with the warmer daytime highs near 0°C locked into the extreme SW portion of the province. A second shot of snow will push into the Red River Valley tonight as the main low centre of the Alberta Clipper moves through the region. Temperatures in the RRV will rise to –4 or –5°C by midnight before starting to drop as the cold front moves through. The bulk of the snow will start near midnight and taper off on Saturday morning with a further 3–5cm of snow accumulation for a total of 4–7cm by the time this whole system moves through.
A few flurries will be around on Saturday as Arctic air begins building into Southern Manitoba yet again. Fairly strong northerly winds gusting up to 60–70km/h will develop early Saturday morning which will result in significant blowing snow in the RRV outside the City of Winnipeg. “Ground blizzard” conditions will be relatively widespread, with particularly poor visibilities as low as 100–200m on west-east running roads, such as the Trans-Canada Highway from Winnipeg to Portage La Prairie. Given the already slick conditions of many roads around the province, be sure to give yourself plenty of extra time if you need to travel on Saturday. The winds will lighten up by mid-afternoon, marking the start of our entry into a major deep freeze. Bitterly cold Arctic air will be pushing southwards behind this clipper system, with temperatures falling to around –25°C by the end of the day. Temperatures will plummet tomorrow night, with overnight lows through the Red River Valley dropping to the –30 to –35°C range. Temperatures will rebound slightly on Sunday as a weak disturbance brings some cloud and a chance of a flurry or two, but even colder air looks to be pushing in on Sunday night.
If the models are to be believed (which I do have some hesitation at the moment), temperatures will drop through the day on Monday to nearly –30°C by the end of the day, with overnight lows dipping to nearly –40°C. I think that the models are getting a little too excited about how cold it will get. The GEM-GLB model’s overnight lows have been 5–6°C too cold over the past week, so it’s more likely that we’ll see lows closer to –35°C than –40°C. At that point, though, it’s colds enough that those numbers don’t even matter. It’s certainly going to be an extremely cold start to next week.
