More Snow Tonight

More snow is on the way for Winnipeg and the Red River Valley as a fairly strong low pressure system tracks through North Dakota and spreads snow through much of Southern Manitoba. The upside to the snow is that rather than plummeting into another deep freeze, this system will actually mark the start of a notable warming trend for Southern Manitoba!

Wednesday
-17°C / -19°C
Increasing cloud; snow beginning early in the evening. 10-15cm overnight.

Thursday
-16°C / -23°C
Occasional sunny breaks with a chance of flurries.

Friday
-18°C / -21°C
Mainly sunny.

Significant Snowfall Tonight

While today may bring mainly sunny skies through much of the day, a low pressure system set to bring a fair amount of snow is on it’s way. Temperatures will warm up to around -19°C before cloud starts streaming in from the west later in the afternoon. There’s a decent chance we’ll see some light snow through the evening, but the main shot of snow will arrive through the overnight period.

Forecast storm-total snowfall amounts by Thursday morning.
Forecast storm-total snowfall amounts by Thursday morning. Updated image; original forecast is here.

Conditions will deteriorate from west to east through the evening as heavier snow pushes into the province. In general, between 5-10cm of snow can be expected for all areas along and south of a line running approximately from Dauphin to Gimli to Pinawa, however there are two primary areas of concern I have for higher amounts:

  1. Patchy areas of very heavy snow. Several models are indicating extremely strong lift associated with this system. While the moisture supply isn’t astonishing, there’s certainly enough for me to be concerned about some embedded areas of very heavy snowfall. It’s impossible to say where these might occur at this time, but be aware that there is the potential for snow to rapidly accumulate should some of these heavier bursts of snow develop. Of course, the heavy snow would also produce near-zero visibilities, so if you need to drive overnight, be prepared for poor conditions.
  2. Higher amounts near the western escarpment of the Red River Valley. With the low pressure centre tracking far to our south, we’ll primarily see easterly and north-easterly winds through much of the event. These are favourable directions for upslope enhancement along the western escarpment of the RRV. This is a more predictable feature, and I feel comfortable saying that areas near the escarpment will see closer to 10cm, perhaps as much as 15cm if the winds align just right. The winds will shift to northerly very early on Thursday morning, so the threat will have limited time to work.

Here in Winnipeg we’ll most likely see around 10-12cm by the time all is said and done, assuming the track of the low doesn’t dramatically shift southwards. Although winds may get a little gusty this afternoon, it should be relatively light through the snowfall event itself at only around 20-30km/h. Snow will taper overnight in southwestern Manitoba and early tomorrow morning here in the Red River Valley.

A Couple Cool Days as Pattern Shifts

Thursday will bring mainly cloudy skies, although we’ll see a few sunny breaks through the day. There will be a good chance of some light flurries through much of the day and into the evening. No real accumulations should come of them, though. We’ll see a high near -16°C thanks to all the cloud followed by a low near -23°C with clearing skies overnight.

Friday will be mainly sunny and cool with a high of only around -18°C. We’ll drop down to a low near -21°C on Friday night with a few clouds pushing in.

Weekend Marks Beginning of Warm-Up

This weekend will bring warmer temperatures as a westerly flow develops aloft and brings milder Pacific air into the region. Saturday looks to bring mixed skies as an Alberta Clipper scoots through extreme SW Manitoba and North Dakota. It looks like our temperature will climb to around -13°C or so. Sunday looks to be mainly cloudy as Pacific air continues to wash over the Prairies. Models are hinting at a storm system that might bring us another batch of snow on Sunday night, but we’ll leave that one until we’re closer to the event.

Temperatures look to climb above -10°C on Sunday and close to -5°C on Monday. Better yet, it looks like the warm-up may actually be here to stay for a while!