Updated Monday, April 3rd at 4:45 p.m. - Environment Canada has upgraded the severe weather alert for much of Southern Manitoba to a Winter Storm Warning. Late Monday afternoon the upgraded alert was issued for the Red River Valley and all of Southeastern Manitoba including the Morden, Carman, Winkler, Altona, Emerson, Morris, Vita and Sprague regions.

A Winter Storm Watch remains in effect for the Killarney, Pilot Mound and Manitou areas.

For the latest Road Report and Cancellation information, click here.

In the updated Warning, Environment Canada stated a significant late season Colorado Low is still on track to impact impact the region, bringing 15 to 25 cm of heavy snow, followed by strong winds and visibility reductions due to blowing snow.

"Beginning late Tuesday afternoon, heavy snow will begin to fall over southern Manitoba and will continue until Thursday morning," stated the latest alert. "The greatest accumulations will fall over the extreme southeastern portions of the province, with totals on the order of 20 to 25 cm of snow."

The weather agency indicated storm total accumulations will decrease to the west and northwest, with the Red River Valley seeing 10 to 15 cm of snow and western Manitoba looking at a 5 to 10 cm storm total.

For your forecast, click here.

Of additional concern for the Red River Valley and western Manitoba, winds will begin to gust up to 70 km/h, and visibilities will rapidly decrease in blowing snow as the bulk of the heavy snow pulls out of the region late overnight on Tuesday into Wednesday morning.

Southern portions of Lake Manitoba and along the Red River escarpment may see particularly bad conditions with strong northerly winds funneling along the geography and may warrant an upgrade to a blizzard warning.

Conditions will improve through the evening on Thursday as the Colorado Low pulls out of the region to the east and a ridge of high pressure builds in from the west.

For our original story with CMOS Accredited Weathercaster Chris Sumner, read below.

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A slippery start to the Monday morning commute with students and staff returning from Spring break will seem like a minor inconvenience compared to the strong Colorado low poised to bring significant impacts to much of Southern Manitoba beginning Tuesday afternoon, and potentially lasting into Thursday morning.

"The Alberta clipper which brought 5 to 10cms of snowfall to much of western Manitoba Sunday, is now to our east, but before it passed through, freezing drizzle last night, as well as in the early hours of Monday morning, have left a glaze of ice many highways in the Pembina and western Red River Valleys," said CMOS Accredited Weathercaster Chris Sumner. "Snow and ice covered conditions can be found west of Pilot Mound and Swan Lake."

For the latest Road Report and Cancellation information, click here.

Breezy conditions will last for most of the day, as the northerly winds on the back side of the Alberta clipper gust up to 50 km/h, and the cold front passing through allows cooler air to sink into the region, but not as cool as this time last week.

"Monday night into early Tuesday afternoon will be quiet, and then we'll start to see the impacts from what will be a very strong Spring snowstorm," Sumner noted.

A Winter Storm Watch continues Monday ahead of the arrival of that strong Colorado low. The Watch currently includes most of Southern Manitoba including Brandon, Killarney, Pilot Mound, Manitou, Morden, Winkler, Altona, Emerson, Morris, Steinbach, Vita and Sprague areas, as well as the City of Winnipeg. According to Environment Canada, snowfall totals from the storm are projected between 15 to 25 cm, with the highest totals currently forecast for the far southeastern corner of the province.

For your forecast, click here.

"The latest forecast model runs Monday morning continue to bring confidence this will be a significant storm, with substantial to major impacts across our region, as well as much of North Dakota, northern Minnesota and Northwestern Ontario," said Sumner. "There is no 'if' this will hit our region. We are at the point of fine tuning the 'when' and how significant the impacts will be."

Based on the current track of the low, Sumner expects snowfall to start by mid to late Tuesday afternoon, with snowfall rates increasing into the evening and overnight hours to Wednesday morning.

"Because of the intensity of this Colorado low, we're also expecting strong winds to be wrapped around it, so at this point, gusty northerly winds are likely throughout the event, peaking at 60km/h or more," he noted. "There still is some uncertainty where the strongest winds will be felt, but the general guidance, as of now, is the western Red River Valley, toward the Manitoba escarpment, as the target zone for the strongest part of the wind-field on our side of the border."

Sumner stressed, travel from Tuesday night through Thursday morning may be extremely difficult, especially with the combination of snowfall and winds bordering on blizzard criteria.

"Giving some second thought, now, to your plans during that timeframe would be a good idea, because it's likely you will be postponing or cancelling," he said. "This is lining up to be the most significant storm of the Winter 2023-23 season."

Conditions are forecast to deteriorate throughout Tuesday night, and remain poor throughout Wednesday. The system will begin moving out of the region Thursday morning, with quieter weather expected for Easter weekend. Sunshine and temperatures around seasonal, or slightly above, are expected. Average daytime highs for the start of April are around 7 degrees, with overnight lows of -4.

Also to be considered with the impending arrival of this Spring snowstorm, is the effect it will have on flood forecasts throughout the Red River Valley.

"Based on current projections, the heaviest band of snowfall with this Colorado low will move over a good portion of the U.S. Red River basin, and all of that melt water will come northward, adding to whatever we receive on the Canadian side," Sumner explained. "We won't know what the actual impact is until after the storm has moved on, and the necessary estimates can take place, but there's no doubt this snowfall event will change the last round of forecasts from both sides of the border."

Manitoba's Hydrologic Forecast Centre Tweeted Sunday afternoon it is monitoring the potential impacts of the system.

"The Hydrologic Forecast Centre is monitoring a potential weather system that could impact southern MB and the U.S. portion of the Red River basin, and is assessing the impact of Spring flows and levels," said the Tweet. "The department will release updated flows, and level forecasts, once the system passes, and the exact amount is known."