Seasonal Weekend Ahead

Seasonal weather will be in place over the Red River Valley this weekend with dry conditions and comparatively mild temperatures.

Friday
-9°C / -14°C
Mixed skies and breezy

Saturday
-6°C / -8°C
Increasing cloud with late-day wind

Sunday
-3°C / -9°C
Cloudy and mild

Today will be the least pleasant day of the weekend with temperatures climbing to around -9°C with somewhat gusty northwesterly winds – around 30km/h with gusts closer to the 40-50km/h mark – ushering cooler air than we had yesterday. While we’ll see a fair amount of cloud today clearing out in the afternoon, no snow is expected. Temperatures will dip to the mid-minus teens tonight as winds taper off.

Saturday looks like a fairly pleasant day. A ridge of high pressure over the region will bring mainly sunny skies and a high near -6°C. Winds will begin picking up out of the south a little later in the day, making it feel a bit colder but limiting our overnight low to just around -8°C or so. Some light snow is possible late Saturday afternoon into the evening hours ahead of a warm front gradually lifting northwards through the night.

Sunday will be a very mild day that starts off with somewhat unpleasant southeasterly winds. By late morning or early afternoon it looks like the winds will die off and the temperature will climb to a very balmy high of around -2 or -3°C. Some snow is possible in the afternoon, but it looks like the bulk of the precipitation will remain to the north and east of the Red River Valley, with just a light dusting of snow possible. Temperatures on Sunday night continue mild with lows near -9°C.

Pattern Change Next Week Brings More Mild Weather

As we mentioned earlier this week, a major pattern shift covering much of North America will occur through the early half of next week that will move most of the continent into an above-average temperature regime for an extended duration.

The general gist of the pattern evolution is this: over the next few days, a very strong frontal zone over the northern Pacific will shift eastwards alongside a train of upper-level disturbances reflected at the surface by a very intense low pressure system – bottoming out today at 950mb or so. This intense low will become stacked east of the Aleutians and absorb several weaker, more disorganized disturbances, becoming a very impressive, large storm over the northeastern Pacific. This intense system will build an upper-level ridge over western North America, beginning the push of warm air. The second key ingredient is the evolution of the polar vortex that has been anchored over Hudson Bay for the last few weeks.

By this weekend, shown here in the GDPS 500mb height & vorticty forecast, several very potent low pressure systems – marked by the letter L – will begin building a ridge over western North America while the polar vortex – shown by "PV" – begins a slow trek eastwards.
By this weekend, shown here in the GDPS 500mb height & vorticty forecast, several very potent low pressure systems – marked by the letter L – will begin building a ridge over western North America while the polar vortex – shown by “PV” – begins a slow trek eastwards.

Fortunately, a powerful low pressure system heading up the east coast with teleconnections to the polar vortex will help “push” the vortex from its resting place and rapidly shunt it eastwards over Greenland. This is the second key ingredient because the polar vortex over Hudson Bay[1] is what anchors the eastern Prairies into a northwesterly to northerly flow for such long periods of time, reinforcing colder air and shunting warmer air to our south. With the vortex skipping town, the arctic jet stream will retreat northwards and the warm air spreading northeastwards with the upper ridge will be able to spread eastwards across the Prairies unhindered.

It’s a very interesting situation that highlights how stable the ridge-trough pattern that is so common is; in order for us to be kicked out of this pattern that has brought us a very cold November, we need very potent, significant storms on both coasts at the same time disrupting the upper-level pattern enough to get things moving again.

Within the warming pattern, we’ll see relatively warm and cool spells as disturbances ripple across the Prairies , but overall it looks quite dry in the Red River Valley as daytime highs climb into the -5 to 0°C through the second half of next week with the possibility of above-zero temperatures late into the week through the weekend. different from


  1. Its worth noting given how much press the term “polar vortex” gets lately that this is a completely normal feature that is dominant over Hudson Bay for huge swaths of winter every single year.  ↩

Warm-Up in Store

There’s no question about it: the biggest upcoming weather story is the big warm-up that’s in store not just for Winnipeg & the Red River Valley, but much of North America. After one more cold night tonight, temperatures will move towards seasonal values by the end of the week and then push towards above-normal by the end of the weekend. Given that November just finished up as the 22nd coldest on record that was some 4°C below normal[1], news of a prolonged warmer trend is likely very welcome news for many.

Wednesday
-15°C / -20°C
Mainly sunny; becoming partly cloudy in the evening

Thursday
-8°C / -15°C
Mix of sun and cloud

Friday
-9°C / -15°C
Mix of sun and cloud

Medium-range model consensus is showing high agreement in an above-normal temperature trend through the first half of December.
Medium-range model consensus is showing high agreement in an above-normal temperature trend through the first half of December.

Today will be a relatively cool day courtesy a cold front that passed through Southern Manitoba overnight. Daytime highs will sit near -15°C through the Red River Valley today under mainly sunny skies and relatively light west to northwesterly winds. A ridge of high pressure moving through the region tonight will help temperatures dip to a chilly -20°C overnight.

Southerly winds will develop through the Red River Valley in advance of an approaching warm front quickly advancing across the Prairies. The winds – climbing to only around 20-30km/h – will help our overnight low as relatively “mild” as it is as well as begin ushering in warmer air. Temperatures will climb to around -8°C by Thursday afternoon as the winds gradually diminish under mixed skies. Temperatures will dip to the -15°C on Thursday night.

Looking to the end of the week, Friday appears to be a near-copy of Thursday with light winds, mixed skies and a high of -9 or -8°C and a low once again near -15°C.

Seasonal to slightly above seasonal temperatures will continue through the weekend alongside a slight chance for some light snow.


  1. We’ll have our own climate summary on the fall of 2014 up later this month.  ↩

A Snowy Start to the Weekend

A winter storm that is bringing all manner of treacherous weather to Alberta[1] will extend into Manitoba today and tomorrow in what could only be considered “a complicated setup.” Snow will arrive in multiple batches as weak upper-level impulses slide west-to-east across the province along a very strong mid-level warm front before the main low pressure system works its way into North Dakota spreading a final area of snow across Southern Manitoba alongside gusty northerly winds and colder temperatures. The whole system will push off into Ontario for Sunday leaving clear skies and cold weather to round out our weekend.

Friday
-11°C / ⇒ -11°C
Mainly cloudy with a chance of flurries; snow overnight
Saturday
⇓ -17°C / -22°C
Snow tapering off to a chance of flurries
Sunday
-19°C / -28°C
Clearing and cold
Environment Canada has issued snowfall warnings for the Parkland & Interlake regions.
Environment Canada has issued snowfall warnings for the Parkland & Interlake regions.

While snow falls over Western Manitoba today, it will be a bit of a different story here in Winnipeg & the Red River Valley as some scattered morning flurry activity gives way to a fairly cloudy day with just a slight chance of some more scattered flurries. By late in the afternoon, however, more organized snow will begin building into the Red River Valley from the northwest, spreading southeastwards through the night.

This particular shot of snow will be courtesy of a very strong warm front in the mid-levels of the atmosphere that has been producing exceptionally snowy conditions in Alberta & Saskatchewan. Snow will continue through much of the night (a few breaks in the snow are possible) and into Saturday morning.

On Saturday, a strong cold front will push through the Red River Valley midday. This will lead to another distinct shot of snow associated with the cold front and the mixing zone behind it.[2] By the time all is said and done, around 5-10cm will likely have fallen here in Winnipeg and through much of the Red River Valley. If things really go off the rails, little could be seen as the first band of snow remains further north and the second band of snow passes to our south, but I don’t think that outcome is likely.

The "most probable" snowfall totals from the morning of Friday November 28th to the evening of Saturday November 29th, 2014.
The “most probable” snowfall totals from the morning of Friday November 28th to the evening of Saturday November 29th, 2014.

The snowfall winners will be through Parkland Manitoba and the Interlake, where general amounts of 15-20cm are expected. Due to the terrain in the Parkland, up to a foot of snow could potentially fall in any areas prone to upslope enhancement.[3] The snow will taper off from northwest to southeast through Saturday afternoon.

Daytime highs today will range from around -10°C near the international border to -11°C here in Winnipeg to the mid-minus teens in the northern Interlake westwards into the Swan River region. Temperatures will remain fairly steady tonight through the Red River Valley, perhaps dropping a degree or two. Tomorrow will bring falling temperatures throughout the province as that cold front sweeps through; by the end of the afternoon temperatures will likely have dropped to around -17°C or so and then continue on an overnight low dropping into the -20 in range.

Sunday will bring clear and cold conditions to Winnipeg & Southern Manitoba. Highs will climb just above -20°C before dropping back down into the low -20s on Sunday night.


  1. At one point yesterday, Environment Canada had issued winter storm warnings, heavy snowfall warnings, freezing drizzle advisories, and snow squall watches simultaneously for various parts of Alberta.  ↩
  2. It’s not uncommon to have what’s known as a “mixing zone” behind strong cold fronts in the winter time; the intense temperature contrast between the Arctic air and the air its replacing can result in as much as several hundred kilometers of low cloud and light-to-moderate snow in the wake of the front.  ↩
  3. …which essentially means anyone near the Riding Mountains or the escarpment.  ↩

Cold Snap Leads Into Another Alberta Clipper

The coldest temperatures so far this season will be settling in for a short stay in Southern Manitoba before a powerful series of clippers move across the Prairies at the end of the week, bringing what may become one of the most potent winter storms seen so far this winter.

Wednesday
-18°C / -30°C
Mainly sunny
Thursday
-17°C / ⇑ -14°C
Increasing cloudiness
Friday
-10°C / -13°C
Chance of flurries

The deep freeze settles over Manitoba today as a potent high pressure system moves in from Northern Saskatchewan, bringing with it a fresh shot of Arctic air. Temperatures will warm to around -18°C from the mid-minus-twenties present this morning under mainly sunny skies. Tonight will bring the coldest temperatures of the season to Winnipeg and the Red River Valley with overnight lows dropping dangerously close – or even just below – the -30°C mark. Tonight’s record low for Winnipeg is -36.1°C set in 1891, so some solace can be had knowing it’s been colder.[1]

Tomorrow will see the cold air exit the region as a major system making landfall in British Columbia begins pushing warmer air eastwards across the Prairies. Temperatures will be on their way up, up, up with a daytime high near -17°C followed by a rising temperature trend overnight that brings temperatures up to around -14°C by Friday morning. While Thursday will start off clear, cloud will start spreading into the Red River Valley sometime midday or into the afternoon, with things becoming completely cloudy sometime in the evening.

Some light snow is possible on Thursday night along a mid-level trough in the region. While more consistent snow is likely over southwestern portions of the province, here in the Red River Valley little is expected in the way of accumulations. We’ll keep an eye on it, but it looks like amounts will remain less than 2cm in any activity that develops.

Friday Brings Winter Storm to Portions of Manitoba

Friday will likely be a bit of a mess of a day…somewhere. A potent low pressure system will track eastwards near the international border, spreading an area of snow ahead of it and another area of snow to its north. It’s really too early to make too many accurate predictions other than a whole host of weather being possible on Saturday. Some areas of the Red River Valley will likely see some snow while a more organized snow event occurs (once again) through Parkland Manitoba eastwards through the Interlake and into the Berens River Region. There’s simply too much uncertainty with the track and strength of the low at the moment to create a snowfall forecast; it looks like a possible snowfall warning event will occur through the Interlake[2] while lesser amounts track along and south of the Trans-Canada corridor. We’ll be making a snowfall forecast graphic a little closer to the event when we can have more confidence in the amounts.

Just one of many model solutions, the GDPS shows lighter precipitation amounts (just 2-5cm of snow, generally) in Southern Manitoba from Friday morning to Saturday morning.
Just one of many model solutions, the GDPS shows lighter precipitation amounts (just 2-5cm of snow, generally) in Southern Manitoba from Friday morning to Saturday morning.

On Friday evening, temperatures will continue to rise with southerly winds into the mid-minus single digits, but then the low will pass and the winds shift around to northwesterly at 30-40km/h. Ample low-level moisture coupled with an incoming – and very dry – 50kt jet at 700mb may result in some freezing drizzle or snow grains overnight. The northwesterly winds will bring in substantially colder air with temperatures dropping to around -12 or -13°C after the evening rising trend.

Colder Air Returns for the Weekend

Saturday will bring clearing skies as another ridge of high pressure moves into the province. Temperatures will only recover slightly from Friday’s overnight low thanks to a fairly breezy northwesterly wind before dropping into the mid-minus 20’s on Saturday night under clear skies. Sunday looks sunny with a high in the low minus teens and calmer winds.


  1. Words of minimal comfort, I know.  ↩
  2. Environment Canada issues snowfall warnings when accumulations of ≥ 10cm are expected in a 12 hour period.  ↩