Winnipeg is on track to see an unsettled weekend culminate in a major winter storm as a Colorado Low spreads heavy snow into Manitoba on Sunday night. But the big question remains: how much?

Those hoping that we could escape winter without a major storm this year, brace yourself. It all kicks off today with cloud building through southern Manitoba as a complex storm system begins organizing over the western United States. Temperatures in Winnipeg will be mild with a high near -2°C. Winds will remain light out of the northeast. As some warmer air lifts northwards through the Dakotas towards Manitoba in the evening, it will begin bringing the chance of snow to the region. Temperatures should remain steady near -3°C on Friday night.

The uncertainty begins to ramp up on Saturday with models providing a variety of possible solutions. The general agreement as of writing is that snow will spread across southern Manitoba through the day on Saturday, with more organized snowfall developing on Saturday night. Amounts with this first batch of snow will be limited, with general amounts of 2 to 4 cm forecast on Saturday night. Temperatures will be quite mild on Saturday with a high near +1°C, which means that if precipitation moves into the Red River Valley through the day, some if it may fall as rain. Winds will be out of the east-northeast at 20 to 30 km/h.

Mild temperatures will continue Sunday with highs once again near 0°C. There will be a slight chance of flurries or drizzle through the day as a Colorado Low begins lifting northwards. Winds will continue out of the north near 30 km/h. The main event is forecast to begin on Sunday evening as heavy snow moves into the province from the south. Unfortunately, there is still quite a bit of uncertainty associated with this, including:

• Where will the heaviest bands of snow set up?
• How quickly will this system move?
• Exactly how intense will the snowfall be?

For Sunday night, it looks like the main threat areas are the Red River Valley west towards the Saskatchewan border. There’s a lot of uncertainty with how fast the snow will push northwards, but reaching the Trans-Canada corridor by Monday morning looks likely. The snow will be heavy with the potential for 10 to 20 cm overnight. Winnipeg may escape much of this, instead receiving most of the heavy snow on Monday.

The heavy snow will continue through Monday and then is forecast to taper off Tuesday evening. Storm-total snowfall from Saturday through Monday will likely fall into the 15 to 25 cm range, but there is a small chance of seeing amounts as high as 30 to 40 cm if a worst-case scenario occurs. Either way, it will easily claim the title as worst winter storm so far this year.

Travel Impacts

There will be 3 primary travel impacts from the worst of this storm:

1. Deteriorating road conditions as snow accumulates.
2. Reduced visibility in snow and blowing snow.
3. Snow drifts developing on roadways.

These three elements will be out in full force Sunday night into Monday, and will likely make travel extremely difficult if not impossible. If you currently have travel plans for Sunday night or Monday, it would be a good idea to make a contingency plan and prepare for delays.

Weekend Update

It cannot be understated that the predictability associated with this system is low at this point. We’ll be posting an update or two through the next couple days leading up to the event with updated forecast information, so stay tuned.

Winnipeg’s seasonal daytime high is currently -5°C while the seasonal overnight low is -15°C.