Tag: Arctic Outbreak

Temperatures Plummet for Weekend Arctic Outbreak

Brad Leave a comment

Winnipeg will be re-introduced to winter this weekend as a major pattern shift will usher in one of the coldest outbreaks of the season as bitterly cold air surges out of the Arctic and plummets much of North America into below-normal temperatures.

The next few days will see Winnipeg socked in under extensive cloud cover. While the lack of sun will be a little disheartening, the thick blanket of cloud will moderate temperatures substantially, staving off the cold weather for a little longer.

Both today and tomorrow will be mainly cloudy days with daytime highs around -7 or -6°C and overnight lows in the -10 to -12°C range. A weak ridge of high pressure anchored through the region over the coming days will also keep winds fairly light. All in all, it looks like a relatively pleasant couple of January days.

On Thursday night, a disturbance rippling through the region aloft will help deepen an inverted trough extending to the north-northwest from a low pressure system moving through Iowa. These two things combined will help support an area of light snow that will spread across the province from central Saskatchewan.

AWM Snowfall Forecast for January 7-8, 2016
A large area of light snow is expected to move thorugh the Red River Valley on Friday. Heavier snow is expected through east-central Saskatchewan into Swan River & Dauphin.

Snow will begin through Thursday night from west to east and will be fairly light, with just 2-4cm total accumulation expected by the time it tapers off on Friday afternoon.

Temperatures will be fairly steady throughout the snowfall on Friday, either remaining near Thursday’s overnight low or perhaps recovering just a degree or two. As the snow tapers off in the afternoon, gustier northwesterly winds will build into the region—at this point it looks like they’ll be around 30km/h—and begin ushering in colder air.

Skies will clear on Friday evening allowing temperatures to plunge to about -21°C by Saturday morning.

Long Range: Cold Weekend

This weekend will see bitterly cold weather settle in over the province as the core of the coldest air on the continent rotates over the region. [1]

GDPS 850mb Temperature Forecast valid Saturday 12Z 09 January 2016
The GDPS 850mb temperature forecast shows the core fo the coldest air on the content rotating into Manitoba.

This very cold air mass will result in temperatures steady near around -20°C on Saturday, but quickly dropping into the lower -20’s on Saturday night. Sunday will likely see a high near -21 or -22°C with temperatures remaining fairly steady on Sunday night as some warmer air begins working into the region. Skies will be mainly clear through the weekend with little wind.

Looking further ahead into next week, near-seasonal temperatures to slightly below-seasonal temperatures are expected. Seasonal highs are near -13°C for this time of year.

  1. Some may wonder why the coldest air mass on the content won’t result in the coldest temperatures on the continent, and the answer to that is complicated. The most basic reason is simply that compared to our Arctic neighbours, we actually have sunshine at this time of year. There are a host of other reasons, too, rooted in prior conditions.  ↩

Snow Ushers In Brutal Cold Snap

Brad Leave a comment

Snow will the the story today as another system moves across Manitoba bringing close to 10cm to Winnipeg and lesser amounts southwards towards the International Border. The warm temperatures that we’ll see today will quickly be replaced by one of the most unpleasant cold snaps of the year; while temperatures won’t be the coldest we’ve seen, they’ll be coupled with a strong wind that will produce some of the coldest feeling weather of the winter.

Friday

-11°C / -23°C
5-10cm of snow. Windy with blowing snow in the morning and evening.
Saturday

-22°C / -33°C
Sunny, windy and very cold.
Sunday

-27°C / -30°C
Mainly sunny. Extremely cold.

Friday: Snow & Blowing Snow


Snowfall accumulations aross Southern Manitoba; totals for the period of Thursday night through Friday evening.
Snowfall accumulations aross Southern Manitoba; totals for the period of Thursday night through Friday evening.

Snow will be the story today as a pair of low pressure systems move in tandem through Manitoba; one in the Northern half of the province and the other travelling near the United States border. They will work together to produce an extremely wide swath of snow that covers nearly the entire province. The heaviest snow will track through the “usual” suspects: Parkland Manitoba (particularly near Dauphin) SE through the Southern Interlake and then off towards Pinawa and into NW Ontario.

Along the axis of heaviest snow, around 10–15cm will fall, with the higher amounts closer to the Ontario border thanks to the merging of the two low pressure systems. Winnipeg will sit right on the southern edge of the axis of heaviest snow, so we’ll likely see total amounts by this evening very close to 10cm. Amounts will taper off relatively quickly as one goes south; areas near the U.S. border will see only around 2–5cm of snow.

In tandem with the snow will be mild temperatures and strong winds. Here in Winnipeg the temperature will climb to a comparatively balmy –11 or –10°C while temperatures in the Southern Red River Valley may see as high as –5 or –4°C. These warm temperatures will be ushered in by the strong winds we’re seeing this morning out of the south at around 40km/h with gusts to 60km/h. This wind will produce blowing snow in open areas of the Red River Valley this morning which will produce near-zero visibilities. As is usual, highways running west-east will be hardest hit. The wind will taper off midday and we’ll see a fairly pleasant afternoon with some light snow, mild temperatures and light winds.

Things will deteriorate quickly in the evening as the cold front slumps southwards. Extremely cold air will begin pushing into the Red River Valley as winds pick up out of the northwest to 30–40km/h with gusts as high as 60km/h. This, combined with the freshly fallen snow, will produce widespread blowing snow through much of the Red River Valley through the evening and overnight hours. Visibilites will be near-zero in some areas and, in general, highway travel will be difficult. If you need to travel tomorrow night, carry a winter survival kit and give yourself lots of time to reach your destination.

Brutal Cold Returns for the Weekend

The GDPS 850mb temperatures show an extremely cold Arctic air mass moving over Southern Manitoba this weekend.
The GDPS 850mb temperatures show an extremely cold Arctic air mass moving over Southern Manitoba this weekend.

After the snow and wind moves out tonight, we’ll be left with absolutely brutal cold moving into the region. Although the temperatures won’t be quite as cold as the last shot we got, they’ll be paired with winds in the range of 15–30km/h which will make it feel significantly colder. The temperature will slowly fall all day Saturday from whatever it is in the morning (close to –22°C or so) until we hit our overnight low on Saturday night of around –33°C. Combined with the wind, it will feel closer to around –45 by early sunday morning.

Sunday will see temperatures recover to around –26°C thanks to a little bit of cloud pushing back into the region from the north. Winds will be 15–20km/h mainly out of the west. We’ll drop to around -32°C on Sunday night under mainly clear skies.

The brutal winter of 2013/14 continues.

Alberta Clipper To Bring Snow and Extreme Cold

Brad Leave a comment

Conditions will change dramatically this weekend with no thanks to an Alberta clipper system that will spread snow into Southern Manitoba tonight and usher in extremely cold Arctic air1 to the region on it’s back side. Before that system arrives tonight, however, we’ll get to enjoy a beautiful day with temperatures climbing towards the 0°C mark!

Friday

-2°C / -18°C
Mostly cloudy and warm. Chance of an afternoon flurry. Snow beginning overnight.
Saturday

⇒ -18°C / -32°C
Snow. Windy with blowing snow. Cold.
Sunday

-26°C / -33°C
Mainly sunny. Very cold.

Today will be an exceedingly pleasant day for what has been a markedly cold December. Thanks to a flow of mild Pacific air brought in by westerly winds ahead of the Alberta clipper, we’ll see our temperature climb to around –3 or –2°C today with relatively light winds. Skies will likely remain mostly cloudy through much of the day with the cloud cover being bolstered by the warm temperatures over the snow and a weaker leading impulse tracking through the Interlake. We may see a few breaks in the cloud here or there, particularly through the mid-to-late afternoon period. Unfortunately, that’s where the good news ends. An Alberta clipper is on the way, and it’s a doozy.

Total new snowfall by Saturday evening. Anywhere from 5 to 15cm can be expected along the main frontal zone.
Total new snowfall by Saturday evening. Anywhere from 5 to 15cm can be expected along the main frontal zone.

The system will begin spreading snow into the Red River Valley overnight along a line cutting across the northern Red River Valley. The heaviest band of snow will set up along the main frontal zone aloft which will be aligned roughly from Dauphin to Winnipeg and ESE into the Whiteshell. Underneath the heaviest band of snow around 5-10cm of snow can be expected by Saturday morning with amounts tapering to just 2-3cm near the US border. In addition to the snow, a cold front will begin to slump southwards late overnight which will usher in much cooler air. We’ll see temperatures drop to around –18°C with winds shifting out of the north.

Saturday

Saturday will be…miserable. Our temperature will remain steady near around –18°C as cold air continues to infiltrate into Southern Manitoba. Snow will persist through much of the day — although it will likely lighten to just a few flurries by the late afternoon — with another 2–5cm expected to fall across the Red River Valley which will bring storm-total snowfall amounts to around 5cm in areas on the fringes of the system track and anywhere from around 7–15cm under the heaviest band of snow. The winds will become more of an issue on Saturday as they increase out of north to 30–40km/h with gusts as high as 60km/h. These winds, aided by the fresh snowfall, will create areas of poor visibility in blowing snow, especially on any west-east running highways.

Please note: Driving conditions will likely be extremely poor on Saturday morning. In addition to the blowing snow, roads will likely be extremely slippery; the warm temperatures on Friday will likely produce moisture on road surfaces which will rapidly freeze overnight. On Saturday morning, roads will likely be icy with fresh snow on top and blowing snow on top of that. If you need to travel, carry a winter survival kit and give yourself lots of time to reach your destination.

The system will move out on Saturday night bringing clearing skies and extremely cold temperatures as an Arctic airmass settles over the region. Our overnight low will bottom out at about –32°C with fairly light winds.

Sunday

Sunday will be a mainly sunny but very cold day. The temperature will only recover to the low minus 20’s. Winds will remain light — little consolation given the temperatures, though. It’ll drop to around –33°C on Sunday night under clear skies.

When Will It End?

The latest NAEFS 8-14 day temperature outlook is calling for below-normal temperatures for Manitoba.
The latest NAEFS 8–14 day temperature outlook is calling for below-normal temperatures for Manitoba.

Unfortunately, all signs point to the cold weather sticking around for at least the next 4–7 days, if not longer. The NAEFS guidance shows below-normal temperatures expected in the 8–14 day range while all the shorter-range models show cold weather through the next week. The GFS is hinting at a system that might push through late next week that would bring slightly milder temperatures, but it would be short-lived and doesn’t look indicative of a pattern change.

It looks like we’ll definitely be closing out December 2013 as one of the Top 5 coldest Decembers on record in Winnipeg with little reprieve on the horizon. So go enjoy the last nice day of 2013 and then get your long johns ready, plug in the car, get a warm drink, fill up the hot water bottle, renew your CAA membership and whatever else you need to do to prepare for another prolonged bout of extreme cold.

  1. I’m doing my best to not use the phrase “bitterly cold” in today’s blog.  ↩

Alberta Clipper Brings Back the Deep Freeze

Brad Leave a comment

After enjoying a well above-normal –2°C daytime high on Monday, things are set to plunge back into the deep freeze as an Alberta Clipper low pressure system tracks into Ontario and allows a new supply of very cold Arctic air to surge southwards across the Prairies.

The Clipper

Wednesday

-9°C / -26°C
Mostly cloudy; flurries likely. Windy.

A potent Alberta Clipper will move through Manitoba today with the bulk of it’s snow falling along a line from Flin Flon through Norway House and Beren’s River where anywhere from 4–10cm can be expected. Further south, we’ll see light snow through the Parkland and Interlake through much of the day, but the snow won’t start in earnest until the afternoon along and south of the Trans-Canada Highway when the cold front associated with this system moves through.

And what a cold front it is! Yesterday saw genuine flash-freezes in the high plains of the Rockies; Dawson Creek, BC had it’s temperature fall from +5°C to –16°C in just 3 hours. In Grand Prairie, AB temperatures plummeted similarly, with temperatures falling from +5°C to –15°C in just 3 hours as well. It’s this intense blast of arctic air which will help this system produce snow despite the fact it is lacking considerable moisture.

While temperatures won’t be set to plummet quite so dramatically further east in Manitoba, we’ll certainly see the cold air return with a blast. We’ll be dealing with snow, wind, blowing snow and bitterly cold temperatures/wind chill by the end of the day today. Here’s what you can expect:

Snow: We’ll likely see scattered light flurries through the morning and early afternoon. Marginally more organized snow will try to push in through the afternoon along the cold front, but the system will have difficulty producing much snowfall anywhere other than along the northern edge of the track of the low pressure system. By the time things taper off this evening, anywhere from just a trace of snow to 2–3cm will likely have fallen in Winnipeg & the Red River Valley.

Wind & Blowing Snow: Winds will remain fairly light through the day until the passage of the cold front early this afternoon. Behind the front the winds will flip to the northwest and pick up strength to 30–40km/h with gusts as high as 60km/h. This wind will couple with the loose snow on the ground and the falling snow to produce widespread blowing snow through much of the Red River Valley. The worst areas for blowing snow will be the western and central RRV on any west-east running roads, including the Trans-Canada Highway between Winnipeg & Portage la Prairie. If you have plans to travel west on the Trans-Canada Highway today, be prepared for slippery roads with snow and blowing snow producing very poor visibilities.

Falling Temperatures/Wind Chill: Temperatures will fall quite aggressively behind the cold front with temperatures dropping from our daytime high of around –9°C to an overnight low of around –26°C. The cold temperatures coupled with the wind will produce wind chill values near –35 through the overnight hours.

The Remainder of the Week

Thursday

-21°C / -28°C
Sunny & cold.

The remainder of the week through the beginning of next week will be marked by the presence of yet another significant Arctic air mass entrenched over the Prairies. We’ll see mainly sunny skies on Thursday with light winds but temperatures will be very cold. Our high will only climb to around –22 or –21°C before plummeting back down to –28 or –29°C for our overnight low on Thursday night.

Friday

-17°C / -25°C
Some afternoon cloud.

Temperatures will climb a little higher on Friday as a very weak disturbance ripples down the northwest flow, spilling a little bit of cloud across Southern Manitoba by the afternoon hours. The temperature will climb up to around –17°C and we’ll see the temperature drop to around –25°C on Friday night.

Things look clear and cold for the weekend. Another shot of Arctic air will push into the Red River Valley bringing another batch of bitterly cold temperatures and overnight lows near –30°C.