More Snow as Colorado Low Grazes Manitoba

More snow is on the way for Southern Manitoba as a Colorado Low grazes the region as it moves through the Dakotas and Minnesota. After the passage of that system, the upper-level pattern will shift and bitterly cold Arctic air will spill southeastward across the Prairies.

Snow will build into Southern Manitoba through the day today from the southwest, with a few isolated flurries in the morning intensifying into more persistent snow through the afternoon. By 6PM, most areas along and south of the Trans-Canada Highway will be seeing snow. The snow will persist through much of the night before tapering off on Tuesday morning.

NAM-based accumulated snowfall for the next storm based on a 10:1 snow ratio.

The NAM model pictured above has been consistently producing a total of between 6-8 cm at a 10:1 snowfall ratio (SLR), however it appears likely that the SLR will be higher at around 14:1, which would push storm-total snowfall ranges in the Red River Valley from around 8-12 cm in Winnipeg to 10-20 cm near the US border. Amounts States-side will be higher, with nearly 25cm of snow expected through east-central North Dakota into Minnesota.

Temperatures will be seasonal with highs in the -9 to -11°C range today and temperatures dropping to -18°C by Tuesday morning.

Winds will be breezy through the day today out of the northeast at around 20-30 km/h. As Winnipeg & the Red River Valley move onto the back-side of this system tonight, winds will strengthen out of the north to northwest to around 40 km/h. These gusty winds will combine with the fresh snowfall to produce blowing snow on area highways with locally poor visibilities. The winds will begin to ease through the early afternoon, bringing an end to the blowing snow.

Cooler Weather For The Remainder Of The Week

Temperatures will be much cooler on Tuesday with little movement from the overnight low near -18°C as colder air moves into the region from the northwest. Even colder conditions will move in on Tuesday night with overnight lows expected to drop to around the -27°C mark. Wednesday will see Winnipeg & the Red River Valley entrenched in the Arctic air with highs near the -22°C mark and an overnight low dipping back down to around the -27°C mark.

The upcoming cold snap can be seen in this forecast for the second half of the week showing the cold air aloft building into Southern Manitoba.

Skies on Tuesday will remain fairly cloudy until the late afternoon when things begin to break up. It doesn’t appear that this cold snap will be associated with particularly sunny skies, though. The main ridge axis will pass well to our west, making it more difficult for all of the cloud to clear from Southern Manitoba. The Red River Valley will mainly see mixed to cloudy skies through much of the week.

Long Range

Little pattern change is expected in the next 7-10 days.

NAEFS 8-14 Day Temperature Anomaly Forecast — Valid January 9-16, 2016

As this NAEFS outlook shows, below-normal temperatures will likely remain in place for the next 1-2 weeks. Temperatures may moderate next week to be closer, but still below, seasonal values. Conditions look fairly dry with little snow expected; the next potential for some snow may be with a clipper system early next week.

So after this snowfall, Winnipeg & region will be falling into a relatively quiet and cold pattern, holding strong for at least the next 7-10 days.

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

Blizzard Ending, Then Much Calmer Weather

The blizzard that has brought much of southern Manitoba to a halt will end today, making way for much calmer weather.

This Week

The crippling blizzard that began last night will gradually end today. Winds this morning will be northwesterly at 40 km/h gusting to 60 km/h, decreasing as the day progresses. Snowfall will end from west to east across southern Manitoba this morning, which will also help to improve visibility. Skies will remain cloudy through the afternoon, with just a lingering chance of flurries. Roads beyond the major routes will likely be impassable today as snow drifts will be significant in many exposed areas. Luckily, calmer weather is expected for the rest of the week, giving folks a chance to recover from yet another significant December blizzard.

HRRR forecast 10m wind speeds valid 18Z Monday December 26, 2016

Tuesday will be a fairly typical winter day with high temperatures in the mid minus teens and a mixture of sun and cloud. Winds will be fairly light, helping to keep wind chill values at bay. Thankfully, this should provide decent weather for those still shoveling out from the storm.

A rapid warm-up will occur on Wednesday as a fast-moving system pushes a warm front across southern Manitoba. This front will push temperatures up close to the freezing mark in many areas, although temperatures for most of the day will be just below zero. This frontal passage may be associated with a bit of snow, but amounts will be small if there’s any accumulation at all.

Long Range

Temperatures in southern Manitoba look to follow a bit of a roller-coaster pattern for the remainder of the week. Another cool-down is expected late this week, before another possible warm-up rolls through for the weekend. This pattern may persist for the remainder of the month before a much extensive arctic air mass moves in for early January.

Forecaster Note

This will be my last regular Monday post at A Weather Moment. I have enjoyed writing my weekly forecast here, but new opportunities mean it’s time for me to give up my regular role. Thanks those that have ready my articles here every week for the past 5 years. I’ll still be a part of AWM, but in a lesser capacity. When the next storm rolls in, you’ll still be sure to hear from me!

-Scott

Update: Blizzard Snowfall Totals

Environment Canada has released a summary with snowfall totals associated with the Christmas Blizzard of 2016:

LocationSnowfall Total (cm)
Winnipeg18-33
Brandon21-25
Steinbach31
Ross30
Beausejour 20
Pinawa24
Grand Beach28
Victoria Beach18
Carman21
Winkler24
Boissevain 36
Melita 35
Miami30
Stony Mountain25
Woodlands20

Winnipeg Set To Receive A Blizzard for Christmas

The consensus is in: it seems overwhelmingly likely that Winnipeg will see a major winter storm bringing significant snow and blizzard conditions beginning midday on Christmas Day and persisting through Boxing Day.

The Lead-Up

Today and tomorrow will both be fairly benign days. Today will bring above-normal temperatures with a high near -4°C and light winds. A bit of cloud will be around but it should be a fairly sunny day overall. A weak cold front will swing through late this afternoon, bringing in northwesterly winds to around 20 km/h and cooler temperatures. The low tonight will drop to about -15°C with increasing cloud.

Tomorrow will be a mainly cloudy day with a much cooler high temperature near -12°C behind that cold front. Winds will continue out of the north to northeast at around 20 km/h. Temperatures will drop to a low near -15°C once agin on Saturday night with a good chance of light snow spreading into the Red River Valley from the southwest through the second half of the night.

Major Winter Storm For Christmas

The major story here is the significant winter storm set to impact Southern Manitoba on Christmas Day.

The system is currently develop off the western coast of North America. This satellite animation, taken from midnight last night, shows the long-wave trough that will evolve into a major winter storm beginning to dig southwards as it approaches the western United States. At this point, it looks like snow will intensify through the day on Sunday, with the most potent part of the storm impacting the Red River Valley roughly from 12PM Christmas Day through 12PM Boxing Day.

If you have travel plans for Christmas Day or Boxing Day, this storm will almost certainly disrupt them.

Christmas Day will start with some light snow over the Red River Valley that will intensify rapidly midday as a very potent low pressure system lifts northwards into North Dakota & Minnesota. The heaviest snow will move in by Sunday evening and persist until late Monday morning. By all indications, the snow will be relentless on Sunday night with rapid accumulations. Through this period, the wind will also be increasing out of the northeast to 40-50 km/h. The heavy snow overnight combined with strong winds will produce blizzard conditions through the Red River Valley with zero or near-zero visibilities. There is a high likelihood that most highways will be closed through the night.

The wind and snow will taper off on Monday. Fortunately, without a potent high pressure system building in from the northwest, a weak trough line hanging back across the province from the low will break up the strong winds. This should limit the period of worst travel conditions, with it seeming likely that by Monday afternoon highway travel will be possible again, although likely still slow.

AWM Snowfall Outlook for December 25-26, 2016

When all is said and done, the snowfall from this system should be quite impressive. Widespread amounts of 15-30 cm will be seen across the region, with areas south of a line running roughly from Pilot Mound through Winnipeg and Pinawa having the chance of seeing snowfall totals creep above 30 cm. At this point it looks like 30-35 cm would be the upper end of the potential snowfall totals, but there is high confidence in amounts of 20-30 cm.

Light snow and flurries may linger through the remainder of boxing day before gradually tapering off overnight or early on the 27th.

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

Major Winter Storm Moving In

Environment Canada has issued a Winter Storm Warning for this system.

A major winter storm is moving in as you read this article. It will bring the first serious snowfall of the year to the Red River Valley, with heavy blowing snow or even blizzard conditions possible in many areas. You may want to reconsider any travel plans early this week!

A strong low pressure system will bring heavy snow and strong winds to southern Manitoba early this week
A strong low pressure system will bring heavy snow and strong winds to southern Manitoba early this week

Today

Monday
0°C / -2°C
Snow beginning

A strong low pressure system will move off the Rocky Mountains and into North Dakota today. It will spread moderate to heavy snowfall into parts of western Manitoba this morning, before snow spreads over the rest of southern Manitoba later in the day. Snowfall will fall for the entire day in most of western Manitoba, with total accumulations of 10-15 cm expected in most areas. Further east, the Red River Valley will see lesser amounts today, with 2-5 cm in the Winnipeg area and more like 5-10 cm near the International border. Local amounts of 15 cm may occur along the International border in south-central Manitoba. Winds will be gusty from the east at 20-30 km/h, producing some blowing and drifting snow.

Tuesday

Tuesday
-2°C / -4°C
Blizzard Developing with Heavy Snow

Conditions will really begin to deteriorate early Tuesday as winds shift to the northwest. Snow will continue to fall as well, with an additional 10-20 cm possible in the Red River Valley on Tuesday. Snow will taper off in southwestern Manitoba, but another 2-5 cm will be possible. The northwesterly winds that develop will be strong at 40 km/h gusting to 60 km/h, with higher values of 50 km/h gusting to 70 km/h in some treeless areas. This will likely result in blizzard conditions over large parts of southern Manitoba, especially south and west of Winnipeg. Those areas that don’t quite meet blizzard criteria will certainly see heavy blowing and drifting snow, with travel becoming difficult or impossible in some areas. Road closures are likely, especially the Trans-Canada Highway west of Winnipeg and Highway 75 south of Winnipeg. Conditions will not improve significantly until early Wednesday.

Expect storm-total snowfall accumulations by Wednesday morning.
Expect storm-total snowfall accumulations by Wednesday morning.

Wednesday

Wednesday
-12°C / -20°C
Snow and blizzard ending

Snow should finally taper off on Wednesday morning in all of southern Manitoba, but not until most areas have received significant accumulations of snow. Southwestern Manitoba can expect 15-25 cm, while Winnipeg can expect 10-20 cm. Areas along the International border in south-central Manitoba can expect to receive 20-30 cm. Locally higher amounts may occur where heavier bands of snow persist for a longer period of time. Large snow drifts will be a problem on Wednesday, even once the snow ends. Some rural roads may be impassable due to heavy drifting. Blowing snow will persist on Wednesday, but winds will slowly decrease throughout the day. Temperatures will have dropped noticeably on Wednesday as this system begins to pull down a cold arctic air mass.

Long Range

Conditions will finally calm down on Thursday as winds taper off. However, in the wake of this strong low we’ll see a blast of arctic air, with temperatures likely dropping into the minus twenties on Thursday and Friday. This frigid pattern is expected to persist for awhile, so make sure to get out those winter clothes!