The first widespread winter weather event of the season is now underway across Southern Manitoba, with Winter Storm Warnings and Special Weather Statements in effect for essentially the entire region.
"Whether it's freezing rain, rain, snow, strong winds or blowing snow, basically every area south of the Trans Canada Highway will see some combination of those conditions from Tuesday morning through Wednesday night," said CMOS Accredited Weathercaster Chris Sumner. "Except for the odd day we dipped closer to seasonal, we have been on a long stretch of well above average temperatures and relatively dry conditions and no snow, but that's about to change over the next 48 hours."
Winter Storm Warnings remain in effect for all of Southwestern Manitoba, as far east as the Pilot Mound and Manitou areas, with a Special Weather Statement issued for the Manitoba escarpment eastward through the Pembina Valley region and across the Red River including the Steinbach, Niverville and Vita areas.
For the latest forecast details, click here
"The reason we're seeing the combination of Warnings and Statements is two-fold," noted Sumner. "One, certain criteria need to be met in order for Environment Canada to issue each, and secondly there is still uncertainty where the snow/rain line is going to set up today across Southern Manitoba. Depending on where that line lands, and which parts of the region remain on the relatively colder side of the system, versus the relatively warmer side of the system, will have a significant impact on what snowfall accumulations ultimately look like."
According to Environment Canada, the current forecast places that snow/rain line somewhere along the western Red River Valley near the Manitoba Escarpment, with areas west seeing snow sooner and more of it, and areas east of it seeing more rain, before the changeover to snow Tuesday night.
15 to 25mm of rain is expected Tuesday in the Pembina Valley, before changing over to wet snow late this afternoon, and then snow overnight. Currently the forecast indicates a range of 5 to 15 cms of snow in our area by Wednesday night, in addition to today's rainfall, with the most likely region to see the higher end of that range being the western Red River Valley, near the Manitoba escarpment.
"As colder air is pulled into this system on its west side, that's when we will see that changeover to snow, and at this point that's looking like wet snow this afternoon and then just snow Tuesday night into Wednesday," added Sumner. "With temperatures hovering near freezing during the duration of this event, even slight changes in how the system moves through the province will greatly impact expected snowfall totals, and where those accumulations land."
For the latest Road Report and Cancellation information, click here.
Gusty northwesterly winds will also be a significant part of this system, with gusts up to 70 km/h possible in Western Manitoba, and somewhat less in the Pembina and Red River Valleys, potentially topping out between 50 and 60 km/h. Northwesterly winds will pick-up throughout Tuesday, gusting to 50 km/h tonight, and up to 60 km/h throughout Wednesday.
"It's important to note, the strong winds are expected to occur when snowfall is happening, meaning blowing snow and reduced visibility will be a factor for a period of time, more than likely from Tuesday night through Wednesday afternoon," he said.
Sumner noted conditions will start to improve west to east Wednesday night and overnight into Thursday morning.
Behind this system a significantly colder airmass than we've had to this point in the season will arrive. Daytime highs Thursday into the weekend will sink to the -4 to -10 range, well below the -2 average daytime high for this point in November.