Wintry impacts begin today across much of Southern Manitoba as a strong Colorado low brings substantial snowfall, strong winds and sloppy conditions between now and Friday night.
A Special Weather Statement is now once again in effect for the Portage la Prairie, Central Plains, Red River Valley and Southeastern Manitoba, with those regions expected to be spared the worst conditions from round one today. Snowfall and Winter Storm Warnings are in place for all of Western Manitoba where 15 to 40 cm is possible by Friday night, along with gusty winds up to 70 km/h.
Further east, showers and wet snow, but little accumulation is expected today, but round two from this complex system hits the Valley and Southeastern regions Thursday and Friday with 10 to 20 cm of heavy wet snow possible. Windy conditions are also expected.
"This is a perfect example of the notorious difficulty there is with forecasting Colorado lows, and falls in line with the guidance provided earlier this week regarding how additional tweaks could be required as the storm's path became clearer," explained CMOS Accredited Weathercaster Chris Sumner. "It's important to note, even though the eastern half of the province is currently not under a Watch or Warning, we can still expect less than ideal conditions in those areas Thursday and Friday, joining the western half of the province which is first up in this three-day event."
Sumner explained a trough extending off the main Colorado low system is what will kick off the impacts today in Westman and the Parkland region of the province. The main low-pressure system pushes into our region out of the Dakotas on Thursday, and that's what will be bringing the second round of snowfall from that point into Friday.
"This system is tapping into moisture rich air from the Gulf of Mexico, and that is giving it ample fuel to really pack a snowfall punch as it slowly works its way across the region," he said. "Just how much accumulation we see will be dependent on a number of factors, including air temperature at the time, but with the general warming of the ground the last few weeks, we can expect quite a bit of melting on contact. As temperatures dip overnight, that's when we'll see the snow pile up. The bottom line is we're likely looking at a sloppy and slushy mess once the precipitation really kicks into gear."
He noted there is still uncertainty regarding the exact impacts over the eastern half of the province, specifically the timing of the precipitation as well as type, but Sumner stressed some combination of a snow-rain mix Wednesday through Friday night is guaranteed. Blowing snow will also be part of the mix, with gusty easterly and northerly winds over the next several days.
"Again, I want to stress, even though half of Southern Manitoba is currently not under a Watch or Warning, this will be an impactful Spring snowstorm, and it's quite possible Watches and/or Warnings will be issued as the exact track and precipitation impacts solidify for those eastern regions."
As for travel conditions, Sumner noted it will be important to check before heading out, especially if you are heading westward where conditions through Westman and southeastern Saskatchewan will be difficult at best.
Storm impacts across Southern Manitoba will last into Friday evening, before this Colorado low finally pulls out of the province.