Prairie Weather (Rural Roots Canada) – Active weather pattern brings chinooks, snow, and arctic air to western Canada
Winter has now taken a tighter grip on the Prairies, with a persistent northwest flow driving repeated shots of colder Arctic air and light snow into the region. Alberta will see on-and-off flurries and periods of mixed precipitation along a northwest–southeast storm track, but any deep cold looks shorter-lived. In Saskatchewan and Manitoba, a series of clipper systems and a strong Arctic front are bringing in some of the coldest temperatures of the season so far, with a few light snow events and brisk wind chills.
Thursday
Alberta
Unsettled conditions continue in Alberta, with snow and cold weather in the north, and warm weather to the south. There is a strong northwest to southeast upper flow. Where the cold weather to the north and the warm weather to the south meet is called a baroclinic zone. Systems will travel in that zone from the northwest to the southeast during the day, bringing clouds and snow. Snow amounts will be minimal, in the 2 to 5 cm range. There is a risk of freezing rain. The risk is not zero, but it is very slight, so motorists need to pay attention. Slush is likely to be a concern on many roads. The map below shows a huge contrast in Thursday afternoon temperatures comparing the north to the central and southern regions. Right along the line separating the warm from the cold is where Thursday’s snowfall is expected.
Saskatchewan
A low pressure system moving through the province from the north to the southeast will bring more snow to Saskatchewan Thursday. Snow amounts will be light, as the low moves through rather fast. Travel disruption will be minimal. The map below shows the amount of snow expected to fall by sunrise Friday morning:
Mild air from the west will boost temperatures above the melting point south of the Trans Canada Highway. Central Saskatchewan can expect highs between 0 and -10, while in the snowy north, afternoon highs will peak near -15.
Manitoba
As shown on the map above, central and southeastern Manitoba can also expect sow from Thursday into early Friday morning, due to the passage of a moist, but weak Low pressure system. After the snow falls in the morning and midday, expect some clearing in the afternoon. This could help bring temperatures up to the -5 to -10 degree range in the afternoon in southern Manitoba and the Interlake. In north central Manitoba, highs will be in the -15 to -20 degree range, and in the far north, it will be quite cold, with highs in the mid -20s.
Friday
Alberta, Saskatchewan, and Manitoba
In meteorology, there’s something called a reverse temperature trend, and we’ll see that happening across the prairie provinces on Friday. Instead of rising through the day, temperatures will go the other way, meaning it will cool down as the day goes on. This animated map shows arctic air plunging southward across the prairies during the day Friday:1
The advancing colder air signals a change in the weather pattern. A change that will bring light snow to parts of central Alberta and Saskatchewan, and a few flurries to southern Manitoba. Thee will be heavier snow over Lake Winnipeg, and in a province wide northwest to southeast band that cuts through Thompson. Even in the areas of heavier snow, accumulations will be minimal, mostly less than 5 cm.
Saturday
Alberta
With the arctic front to the south, Alberta will have a cold day Friday. A ridge of high pressure will sit over Saskatchewan, and the return southeast flow around the high will produce snow in much of Alberta. Expect 5 to 10 cm of snow in northwestern Alberta, 4-7 cm in central and southeastern regions. In the foothills west of highway 2 and south of the Yellowhead highway, there may be no snow at all. This is a tough call, though, as the cold weather and snow could extend as far west, through the foothills, to the foot of the Rockies It depends on whether a downslope wind develops, drying out the foothills terrain. There is a lot of uncertainty. In the foothills, highs could warm to between -4 and -8 if the downslope wind develops. If not, temperatures will be similar to those across the rest of Alberta, where it will be COLD, with highs in most areas near -15.
Saskatchewan and Manitoba
High pressure brings sunshine and clear sky but the lowest temperatures of the season so far are expected in Saskatchewan and Manitoba. Highs are expected to sit in the –15 to –18 C range, with overnight lows trending toward the mid –20s. Wind chill values could range from -25 to -35. That gives a high risk of frostbite after 30 minutes of skin exposure. Here’s Environment Canada’s wind chill chart:
Sunday
Alberta, Saskatchewan, and Manitoba
The high pressure system that brought the clear and cold weather to Saskatchewan and Manitoba moves to the southeast, allowing for some warmer air to come in from the west. Under a partly to mostly cloudy sky, temperatures in Manitoba will remain cold, with highs near or below -20. Saskatchewan will warm up a bit with highs between -10 and -20. The biggest changes come in Alberta, where there will again be sharp differences in the weather between the north and the south. Chinook conditions will develop in the south, and highs will range from -5 to +5. In central regions, highs will be in the mid minus teens. Head further north, and it will be much colder, with snow. Expect snow to fall north of Edmonton, and temperatures will reach a range of -15 to -25. The farther north, the colder it will be.
Heads Up:
This is from an Environment Canada briefing document:
–Violent wind gusts are possible in extreme southwestern AB on Monday and Tuesday
While Monday and Tuesday are beyond the range of this outlook, the word “violent” grabs attention. We’ll have an update early Monday morning with our regular weekly outlook at Rural Roots Canada.
