Cool Conditions To Bring Gradual Melt

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Cooler conditions will linger in Winnipeg through the rest of the week, bringing a gradual melt to the pile of snow that fell over the last 48 hours.

The upper vortex responsible for 23 cm of snow in Winnipeg over the past 48 hours — the biggest snow event of this winter/spring season — is now trundling off towards eastern Canada. A few flurries will linger in its trail through the day. The snow cover and a cool north wind near 20 km/h bring a cool high near 0 °C. Skies will stay mostly cloudy tonight with light winds and a low near -4 °C.

On Thursday, a trough of cooler air aloft will move into southern Manitoba. It will bring a mix of sun and cloud and northerly winds up to around 20 km/h again. Any snow associated with this system will likely stay over southwestern Manitoba with light amounts. Temperatures will climb to a high around 3 °C in Winnipeg. Warmer highs are likely over the western Red River Valley where slight downsloping from the escarpment helps temperatures into the upper single digits. Mixed skies will stay for the night with temperatures dipping to a low near -5 °C.

RDPS 2m Temperature Forecast valid 21Z Thursday April 15, 2021
Southern Manitoba will see cool temperatures on Thursday, save for the western Red River Valley where downslope winds near the escarpment bring near-seasonal warmth.

A broad area of high pressure will build into the region on Friday, bringing a bit more sun. Winds will pick up out of the north into the 20–30 km/h range with a high near 3 °C. Note that it could get warmer than that, highly depending on how quickly the snow pack over the region melts. Given the discrepancy in snow depth, some areas may see highs a few degrees warmer than others on Friday. Skies will clear out on Friday night with temperatures heading to a low near -7 °C.

Long Range Outlook

Temperatures will return closer to seasonal values on Saturday, then another low pressure system is forecast to move through on Sunday. This disturbance will bring more cloud and a chance for some rain or snow. Cooler and cloudier weather starts next week, followed by a gradual return to seasonal temperatures and generally sunny conditions.

Today’s seasonal daytime high in Winnipeg is 10 °C while the seasonal overnight low is -2 °C.

Winter Returns to the Red River Valley

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Winnipeg will see a blast of April snow as a spring storm stalls over the region.

A slow-moving upper-level vortex will slump into the northern Plains of the United States today and stall over the area. This feature will support a deep and persistent stream of moisture from eastern North America into southern Manitoba for the next couple days. As a result, Winnipeg and region will see waves of snow spread westwards across the region today and tomorrow.

Winnipeg will see snow through the day today with accumulations of 5–10 cm by the evening. Moderate northerly winds near 40 gusting 60 km/h will accompany the snow, but the relatively warm conditions should limit the severity of any blowing snow that may develop. That said, visibilities may deteriorate rapidly at times in pockets of heavier snow. Temperatures will hover around -1 °C through the day.

The snow will continue tonight with winds of 30–40 km/h. Blowing snow might become a bit more of an issue overnight as temperatures drop a bit more to a low near -5 °C. Another 5–10 cm of snow is possible overnight.

Periods of snow will continue on Tuesday with temperatures climbing back to a high near -1 °C. Another 4–8 cm of snow is possible through the day. The snow will taper off Tuesday night, but skies will stay cloudy. The wind will ease into the 20–30 km/h range by Wednesday morning with temperatures dropping to around -5 °C again.

RDPS Total Snowfall Accumulation Forecast (at 10:1 SLR) valid 00Z Monday April 12, 2021 to 06Z Wednesday April 14, 2021
All of southern Manitoba will see a coating of snow from the spring storm affecting the area.

On Wednesday, the whole vortex will push off into eastern Canada, leaving the region with mostly cloudy skies and a chance of flurries. Temperatures will climb back above freezing with a north wind near 20 km/h.

By the time the snow tapers off, this system will have the potential to produce as much as 15–25 cm of snow for the Winnipeg area. The final total, though, will likely end up less than that; a combination of melting early in the event and compaction as it progresses should reduce the total accumulation somewhat. That said, it will likely still be enough to produce poor travel conditions and bring the region a short return to winter.

Long Range Outlook

The sun will return to the region by the end of the week, but seasonably cool conditions will persist. Winnipeg will see highs of 2–5 °C on Thursday and Friday, then climb into the 5–10 °C on the weekend. To start next week, the region will likely see variable cloudiness with near-seasonal temperatures.

Today’s seasonal daytime high in Winnipeg is 9 °C while the seasonal overnight low is -3 °C.

Pleasant Weekend Before A Winter Storm

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Winnipeg will see a relatively pleasant weekend after some much-needed rain that fell on Thursday night. Winter isn’t done with the region, though, with a winter storm poised to slam the region by Monday.

A digging trough over western Canada will dominate the upper air pattern over Winnipeg through the coming days. This will bring near-seasonal temperatures and variable cloudiness. Today, the city will see mostly cloudy skies as the system that brought the overnight rain drifts eastwards. A few sunny breaks are likely, though, and should help get the daytime high up to around 10 °C. A brisk north wind will pick up today to around 30 km/h and persist until the evening before tapering off. Skies will clear tonight with a low near -2 °C.

RDPS 2m Temperature Forecast valid Saturday April 10, 2021
Saturday will be a sunny and mild day the Red River Valley.

Saturday will be the nicest day of the next few as a weak ridge moves over the province. Winnipeg will see mainly sunny skies, light winds, and a high near 14 °C. There will be a few clouds overnight with a low near the freezing mark.

On Sunday, the region will begin to fall under the influence of a low pressure system moving southeast from Saskatchewan. Winnipeg will see increasing cloud through the day with a northeast wind picking up into the 20–30 km/h range. Temperatures will climb to a high near 10 °C.

Long Range Outlook

A major winter storm will move through Manitoba Sunday night through Tuesday, bringing significant snowfall to the region. Precipitation will spread through the province on Sunday night, and while some areas may see a bit of rain to begin, everything should change to snow by Monday morning. There is still significant disagreement in the forecasts where the heaviest snow will fall, but there is good agreement with some regions seeing up to 15–25 cm of snow. Unfortunately for Winnipeg, the range in forecast solutions is huge right now…from ≤5 cm of snow to over 20 cm. So at this point it’s a matter of waiting and seeing how this begins to shape up closer to the event.

RDPS Precipitation Type and Rate Forecast valid 12Z Monday April 12, 2021
Snow is forecast across most of southern Manitoba by Monday morning.

That said, it will likely impact most of southern Manitoba and provide much-needed moisture to alleviate some of the drought conditions. In the wake of this system, a slow return towards highs around 10 °C by the weekend is forecast with plenty of cloud cover, allowing the snow melt to gradually soak into the ground.

Today’s seasonal daytime high in Winnipeg is 9 °C while the seasonal overnight low is -3 °C.

Gradually Cooling in Winnipeg, Unsettled Friday Possible

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Winnipeg will see temperatures gradually cool through the rest of the week with a chance for a few showers across the region on Friday.

Winnipeg’s weather over the coming days will be increasingly influenced by a slow-moving low pressure system in the United States. This low, over the Central Plains this morning, will gradually trundle northwards into Minnesota and Wisconsin by Friday. As it moves north, cloud cover will creep northwestwards and cooler temperatures will shift into the Red River Valley.

Winnipeg will see partly cloudy skies today with a weak ridge over the region. The city will see a high near 17 °C with a north breeze picking up this afternoon to 20–30 km/h. Skies will stay partly cloudy tonight with light winds and a low near +2 °C.

That weak ridge will stay in place over southern Manitoba for Thursday. On its flanks, a low over Saskatchewan will lift sharply northwards into Nunavut while to the southeast, the American low slowly lifts through Iowa. Winnipeg will see mixed skies with a high near 13 °C. Winds should be out of the northeast at around 20 km/h for much of the day. The ridge will leave overnight as a trough connecting the Nunavut low and the American low moves into the Province. Temperatures will head to a low near +3 °C with increasing cloudiness and a chance of rain showers.

RDPS 24hr. Accumulated Precipitation valid 12Z Saturday April 10, 2021
Rain will clip southeastern Manitoba on Friday, but there’s uncertainty how far west some lighter shower activity may reach.

On Friday, a sharp deformation zone will set up along a north-south line near the Red River Valley. To the east of this feature, showers will stream from Minnesota northwards towards Lake Winnipeg. To the west, it will stay dry. While the region will see a mostly cloudy day, the chance of rain will be highly sensitive to the exact location of this feature. While rain is likely over southeastern Manitoba, that chance becomes significantly more conditional in the Red River Valley. There will be a breezy north-northwest wind through the day around 30 km/h keeping highs cooler at around 9 °C.

The clouds will begin to break up Friday night as the system begins pushing off to the east. The winds will ease as temperatures head to a low near -1 °C.

Long Range Outlook

The region should see quiet weather for much of the weekend with variable cloudiness and highs of 10–15 °C. By Sunday night, forecasts show a clipper system moving out of southern Alberta and phasing with a low over eastern North America. This will produce the chance for the first significant precipitation event over southern Manitoba in some time. There is significant uncertainty right now, but forecasts suggest a windy winter storm will move through the region on Monday and Tuesday with potentially 10–15 cm of snow.

Temperatures are forecast to hover near or slightly above the freezing mark with this system, so it’s unlikely that much snow would accumulate, as it will compact and melt through the days. The potential exists for a bit of an unpleasant start to next week, but many would welcome the moisture that the storm may provide.

Today’s seasonal daytime high in Winnipeg is 7 °C while the seasonal overnight low is -4 °C.