It appears all of the hard work Mother Nature did last week, giving us the first signs Spring was just around the corner, will be undone by the time the weekend ends. The melting temperatures and brown patches of lawn will more than likely be a distant memory by the time Monday rolls around with confidence growing in a potentially significant snowfall event Saturday and Sunday.
"The first of three systems to impact Southern Manitoba is quickly moving through the region Wednesday morning, with snowfall amounts trending lower than initially expected," said CMOS Accredited Weathercaster Chris Sumner. "Dry air was being pulled into that low by northeasterly winds for much of last night, and helped limit the precipitation it could drop on our side of the border, with a couple of centimetres looking like where we'll top out. A cloudy day is expected, with breezy northerly winds up to 40 km/h leading to some ground drifting and minor blowing snow in open areas throughout the day."
Daytime highs will be warmer than Tuesday, as a westerly flow aloft begins, and warmer air starts moving into our region in the coming days. Highs between -5 and -7 are expected.
"As for the rest of the week, and into the weekend, we've seen some fairly significant changes in what the forecast models are telling us, particularly for the low-pressure system set to impact the region this weekend," he explained. "The second system in this trio will cross the Dakotas Thursday, but is now projected to stay well south of us, and so will its area of snowfall. Outside of a chance of flurries, we're not expecting accumulating snow from that low. Breezy, at times, northerly winds will continue Thursday, but temperatures will remain seasonal on Thursday as we continue to see that westerly flow aloft."
Sumner's attention is now firmly planted on what is coming this weekend, and the potential for it to be a potent system with a substantial snowfall potential.
"Since yesterday, there have been significant changes in what the forecast models are showing regarding this low," he said. "This low will be moving in from the Pacific Northwest, and then along the international border. It will be moisture-packed, and indications, at this point, are for higher snowfall totals than initially expected. There also are signs this system may linger longer than first forecast, lasting through Sunday, before exiting the region overnight into Monday."
Early projections place snowfall totals between 10-15cms Saturday and Sunday, with the bulk of it falling Saturday. Sumner stressed there is also still a fair amount of uncertainty regarding the system's track, and that will play a big role in which areas see the most snow.
"At this point, I'm quite confident we'll see an impactful snowfall event Saturday and Sunday, the remaining question, right now, is how impactful, and whether those impacts will be from the amount of snow we see, or in combination with gusty winds, which are also a possibility," he added. "Gusty winds are being forecast, at this point, and that would lead to blowing snow and reduced visibility."
High pressure is expected to build in over Manitoba on Monday, and that will bring a return to quieter weather to start next week, with the expectation of seasonal temperatures.
"My take away, at this point, is be prepared to change plans this weekend, and make sure your snowblower and shovels are ready to go, because it's pretty likely we'll need both by Sunday night."