More Snow, Then The Bitter Cold Creeps Back In

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An upper low moving into the province will bring more snow to Winnipeg today. Beginning early this morning in Winnipeg, it will continue right through the day and then taper off overnight. This system will drop around 10 cm of new snow across the region. With the low moisture levels seen through the area heading into winter, these recent snowfalls should prove helpful come spring.

Along with the snow, Winnipeg will also see some of the mildest temperatures the city has seen in quite some time. Highs will reach around -14 °C today despite a stiff northerly wind near 30 km/h. As this system pushes off to the east tonight, temperatures will fall back into the mid-minus 20s.

RDPS 24hr. Accumulated Snowfall Forecast (at 10:1 SLR) valid 12Z Wednesday January 5, 2022
Much of southern Manitoba will see snow on Tuesday with 5–10 cm accumulation. The amounts depicted here are a bit underdone; higher SLRs than 10:1 will add about 50% more to the accumulated snowfall in Winnipeg.

Behind this system, colder air will build back into the region as a potent 1045+ mb high slides down the foothills and across the southern Prairies. Temperatures in Winnipeg will drop back into the -20s for highs and likely see lows dipping back below -30 for at least one or two nights later in the week. Extreme cold warnings will make a return for much of the southern Prairies by mid-week; they could reappear here in the Red River Valley for the latter couple days of the work week.

Long Range Outlook

Heading into the end of the week, there are actually some signs of a more substantial pattern change. Several models have the polar vortex over Hudson Bay weakening by the end of the week, shifting off to the northeast, followed by a new centre to the vortex over the High Arctic. This patter change would help break down the persistent northwest flow and/or cold trough over the Prairies and allow milder Pacific air to begin mixing into the region.

GDPS 500mb Height Anomaly Forecast valid 12Z Wednesday January 12, 2022
This forecast of upper level heights (and their anomaly from normal) for the middle of next week shows clearly the collapse of the Polar Vortex back to the High Arctic and the development of upper ridging over the Prairies.

But before any substantial change occurs, there would likely be a period of highly variable temperatures as disturbances move through the region. The first one looks like it might move through on Friday night into Saturday, bringing another chance of snow to the region with highs climbing back towards seasonal values on Saturday. Temperatures would likely cool down behind this system for a few cold days, then warm again mid-week.

Some forecast models suggest that a milder trend may establish itself next week, moving the region into a multi-day pattern of perhaps even seasonably mild temperatures. At this point, one certainly can hope! In the meantime, maybe the cold temperatures can kill off a few pest insects while we wait.

Today’s seasonal daytime high in Winnipeg is -13 °C while the seasonal overnight low is -23 °C.

One More Snow, Then The Deep Freeze Moves In

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The Red River Valley will be grazed by a little more snow today, then a bitterly cold air mass will entrench itself over the region.

RDPS 2m Temperature Forecast valid 12Z Wednesday December 29, 2021
Very cold temperatures will move into Southern Manitoba by Wednesday morning and will persist into the weekend.

If the dump of snow yesterday wasn’t quite enough for you, a little more snow is possible this morning. One last disturbance will move through the region this morning, bringing 4–8 cm of snow to southeastern Manitoba. This area of snow will also graze the Red River Valley with 2–5 cm possible along a southwest to northwest line draped across the area.

The snow will clear out this evening, leaving behind clear skies as bitterly cold temperatures push into the region.

The big weather story for the rest of the week will be the cold temperatures that will stay locked over the region. Daytime highs will be around 15 °C below seasonal in the -30 to -25 °C range right to Saturday. Overnight lows will vary, but there is the potential for some very cold nights with lows dipping below -35 °C. Extreme cold warnings are a certainty for the region in the days ahead as wind chill values of -40 or lower are likely unavoidable.

A few flurries may be possible later this week, but the organized snowfall will be over for a bit after today.

Long Range Outlook

Forecasts have temperatures moderating beginning on Sunday and lasting through much of next week. This warmer weather will come with some snow as well with chances both next Monday and mid-week.

Today’s seasonal daytime high in Winnipeg is -12 °C while the seasonal overnight low is -22 °C.

Mid-Week Snow Ushers In Cooler Conditions

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Temperatures will climb back above freezing today, but a low crossing the region on Wednesday will usher seasonal temperatures back into the region.

RDPS 2m Temperature Forecast valid 21Z Tuesday December 14, 2021
Tuesday will be a very mild December day across southern Manitoba with highs climbing above freezing.

A broad upper ridge over Manitoba today will bring another day of very mild December temperatures. That warmth will be short-lived, though. A deep upper trough moving off the west coast support a complex of lows that moves through the Prairies and American Plains over the next few days.

In southern Manitoba, breezy southeasterly winds will push daytime highs back up above freezing in the Red River Valley. Skies should stay sunny today as the upper flow deflects most of the cloud northwards . The winds will ease tonight with lows dipping back below freezing.

A bit of a complicated weather sleight of hand will then happen on Wednesday and Thursday. The low tracking across Saskatchewan will continue into central Manitoba on Wednesday. At the same time, a Colorado Low will eject northeastwards and move towards Lake Superior. As it approaches, the energy will consolidate towards the Colorado Low, weakening the Manitoba low into Wednesday night. This will send a cold front surging southwards into the United States.

Here in Winnipeg and area, that will mean a cloudy Wednesday with temperatures one again creeping back above freezing. Llight winds in the morning will pick up out of the north through the day as the main trough passes. The cold front will sweep through on Wednesday evening, bringing a couple of centimetres of snow to the region. Strong northerly winds of 40–50 km/h will ease overnight to around 30 km/h. The winds will gradually taper off through the day on Thursday.

RDPS 10m Wind Forecast valid 06Z Thursday December 16, 2021
Moderate northerly winds behind a Colorado Low moving over Lake Superior will usher seasonal temperatures back into the region on Wednesday night.

It’s worth noting that while significant snowfall tomorrow evening isn’t likely, a couple of weather models produce an intense band of snow as an upper-level trough swings through. Canadian forecast models produce significantly more snow from Winnipeg southwest, reaching over 10 cm by Thursday morning. It’s quite an outlier solution and at this point seems unlikely.

The biggest impact from this system will be the shift to more seasonable temperatures. Behind the cold front, temperatures will fall into the -10 to -15 °C range by Thursday morning. Daytime highs will hover in this range for the rest of the week with overnight lows down around the -20 °C mark. The region will see variable cloudiness through the rest of the week. Friday will bring cloudier skies as another disturbance tracks across the region. This system will likely bring a dusting of snow with it.

Long Range Outlook

Little change lies ahead for the region as a more typical winter pattern settles in. Daytime highs will sit in the -15 to -10 °C range right through next week with overnight lows around -20 °C. Other than a chance for a bit more snow on Sunday, conditions will be generally dry with a mix of sun and cloud.

Fortunately, it’s not looking like a huge deep freeze is on the way! Colder conditions should help get local waterways frozen more solidly, but still be pleasant enough to get out and enjoy outdoor activities.

Today’s seasonal daytime high in Winnipeg is -10 °C while the seasonal overnight low is -19 °C.

Sunshine and Mild Early-Winter Warmth Ahead

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Benign and pleasant early winter weather will settle in for Winnipeg this weekend.

The broad shift in the upper-level weather patterns we talked about earlier this week are underway. Gone is the Arctic vortex locked over Hudson Bay, allowing an upper ridge to build eastwards off the Pacific. This will be the dominant weather feature for the next couple days before it flattens out for the end of the weekend. Instead of being replaced by an upper trough and the associated cold air that comes with it, though, a generally zonal to west-southwest flow will develop aloft, continuing to spread mild temperatures across the southern Prairies.

As a result, Winnipeg’s forecast is quite pleasant for the days ahead. Right through the weekend into next week, the area will see daytime highs in the -5 to 0 °C range. A couple of these days may even see temperatures climb above freezing. Overnight lows will be similarly mild, generally falling in the -5 to -10 °C range.

RDPS 2m Temperature Forecast valid 21Z Sunday December 12, 2021
Very mild December temperatures will spread across the southern Prairies this weekend. Most areas will see highs above freezing on Sunday.

Winds will be light for the region today, but for the weekend southerly winds around 20–30 km/h will develop. The windiest conditions should end up over the western Red River Valley where the escarpment can interact with the westerly component to the winds and produce slightly breezier conditions.

Along with these pleasant conditions will be plenty of sunshine; the Winnipeg area will see mainly sunny skies through the weekend. Some cloud cover will begin moving in next Monday and Tuesday.

Long Range Outlook

The next disturbance to impact the region will move through in the middle of next week. Forecasts show it could bring around 5 cm of snow to the region followed by breezy northwest winds and return to more seasonal temperatures. The overall weather pattern after that looks somewhat unsettled with a chance for more snow on Friday/Saturday and potentially again to start off the next week.

Today’s seasonal daytime high in Winnipeg is -9 °C while the seasonal overnight low is -19 °C.