Prairie Weather (Rural Roots Canada) – Winter is here, and there is protective snow on the ground across the prairies. While astronomical winter doesn’t begin until December 21st, meteorologists consider December 1 as the real first day of winter, based on the weather.  It’s called Meteorological Winter, and it runs from Dec 1 to the end of February. For the prairies, though, winter weather arrived even earlier this year. November was a colder than average month across most of the Canadian prairies, and there is plenty of snow on the ground already! Below is a map showing snowfall anomalies, or how much more or less snow on the ground compared to long term averages. Where it’s green, snow cover is above average. And, there’s a lot of green across the prairies, from western Manitoba to central Alberta:

Another way of looking at the data is the following chart, which shows snowfall across North America so far this year is close to the high side of the standard deviation from normal:

With so much snow on the ground across the prairies, the soil and winter crops are well protected from the more severe elements of the coming winter. If the snow stays.   Not all of it will.  There is warm air set to flood into the prairies during this week, especially in the western prairies. It’s illustrated nicely in this animated map. By the weekend, temperatures across agricultural regions of Alberta and Saskatchewan will rise well above the melting point. Manitoba will stay a bit cooler.

And, one more chart before getting into the daily nitty-gritty. This shows how much snow we can expect this week.  And, outside of a band of snow from northeastern Alberta, through central Saskatchewan to southeastern Manitoba, there isn’t much:

Notice in the map above, no snow is expected this week in much of southern and southwestern Alberta. Only minimal snowfall is anticipated for the agricultural regions of Saskatchewan and western Manitoba. Most of the snow will fall in the boreal forest, and the Canadian Shield.

Warmer weather’s on the way.

Monday

Alberta

The first of a few invasions of warm air from the west this week arrives Monday, and there will be a dramatic change in temperatures for most of the province. While the southern half of the province will stay dry, there will be considerable precipitation in parts of northern Alberta.  The warm air will come in aloft, and take a bit of time to work its way down to the ground.  The warm air aloft could generate some Freezing Rain moving from Grande Prairie and Peace River in the morning to Cold Lake in the afternoon.  Near Cold Lake, the freezing rain could continue well into the night and into Tuesday morning. Further north, it will snow.   5-10 cm expected.   Positive temperatures can be expected west of highway 2, reaching as high as 10 by mid-afternoon near Pincher Creek and up along the foothills to Grande Prairie.   East of Highway 2, highs near zero can be expected.  In the far north, the cold air stays in place with highs of -15, or colder.

Saskatchewan

The mild air from the west doesn’t quite reach Saskatchewan Monday, so highs will be in the -10 to -20 range, as the warmer air remains aloft.   The upper warm front will generate snow over central Saskatchewan in the morning, 5-10 cm, with a band of freezing rain or ice pellets along the frontal boundary.  In the evening, expect freezing rain or ice pellets to develop along a line from Lloydminster to Humboldt to Yorkton.  South of that line, it will be dry.

Manitoba

Early morning snow is possible south of the Trans Canada Highway,  but it should be over by sunrise.   The province will be largely dry, except for perhaps some snow over open water on Lake Winnipeg.   Snow from the upper warm front across Saskatchewan will make it to west central Manitoba by evening, and will intensify through the Interlake overnight.   It remains cold, with highs in the -10 to -20 range across the province.

Tuesday:

Alberta

An upper ridge aloft, and a surface low in central Saskatchewan will allow Monday’s Freezing Rain near Lloydminster to continue into early Tuesday morning. In Northern Alberta, the Low will generate some snowfall, while southern and central Alberta stay dry.  By or before noon, the Freezing Rain will change over to rain, and the snow in the north will begin to taper off.  A brisky, drying, chinook westerly wind will boost temperatures to the double digits in the foothills, and the rest of Alberta will likely achieve highs above zero.    There could be, especially in the south, a considerable melting or evaporating of the protective snow cover.

Saskatchewan

The warmer weather finally reaches Saskatchewan, with a brisk westerly wind in central and southern regions.   Temperatures will climb above zero as far north as Prince Albert. Further north, in the forests, it will be colder.   Because of the strong wind,  blowing snow cannot be ruled out, especially in central regions. The Low in central Saskatchewan will move into central Manitoba by the end of the day, but will continue to generate snow across the middle of the province. Near Saskatoon, it may be warm enough for rain.

Manitoba

The milder air is just nosing into western Manitoba, but highs in the province will remain below the freezing point.   Highs near -5 west of Lakes Manitoba and Winnipegosis, and below -5 to the east.   Northern Manitoba stays  cold with temperatures peaking near -20.   Snow is expected across the province, due to a Low at the northern tip of Lake Winnipeg, connecting with another Low to the north in Nunavut.

Wednesday:

Alberta

The circulation around a surface high on the Territories boundary will generate some upslope snowfall across central Alberta in a diagonal line from Grande Cache southeast to Oyen.  On the southern edge of the precipitation band, rain or freezing rain is possible from Calgary northwest to Jasper.   There is considerable uncertainty about this, especially near Calgary, due to the drying effect of the westerly wind.  As the day goes on, the High will move to northern Saskatchewan, ridging all the way south to the Montana border.   That will make that diagonal line of precipitation a bit more perpendicular, in a line from Grande Prairie to Medicine Hat by late afternoon.   Along the eastern boundary of the snowfall, an area of ice pellets, freezing rain, or mixed precipitation is possible along the eastern foothills.   Driving in this area could be dangerous….check weather forecasts and road reports before heading out.  In the foothills, expect highs near 5, near o across central and southern Alberta, and below -10 elsewhere.

Saskatchewan

A brief return to cold weather can be expected, with highs below -15 across most of the province.   The far southwest, including Shaunavon, Maple Creek, and Cypress Hills Provincial Park, could see highs closer to 0, but there will be snow.   Elsewhere it’s cold under a strong ridge of high pressure.   This will knock back the wind speed, and produce a mainly sunny sky for most of the province.   On the east side of the ridge, there will be some cloud, along with the snowfall in the warmer areas of southwestern Saskatchewan.

Manitoba

It’s colder again.   Manitoba’s position on the east side of a Saskatchewan high, means Arctic air will pour into the province, and highs across Manitoba will be in the -10 to -20 range.   A very cool phenomenon similar to Ontario’s Lake Effect snow will occur during the afternoon in Manitoba.   Moisture from open water in Hudson Bay will evaporate into the cold air, and generate snow across northeastern Manitoba.   There will also be lake effect snow west of Lake Winnipeg, as moisture from open water evaporates into the cold air, which is moving in from the northeast.

Thursday:

Alberta

Alberta stays dry and warm due to a westerly wind across the width and breadth of the province.   The entire province will be warm, especially in the foothills, where temperatures should rise to between 5 and 10 degrees.   East of highway two, it will be a bit cooler, but highs will still exceed the melting point.

Saskatchewan

It warms up.   The mild Pacific air will extend into Saskatchewan, and with a westerly wind, temperatures will climb above zero on the western side of the province, with highs just below zero along the Manitoba boundary.   Late in the day, some snow or mixed precipitation could develop along the eastern boundary from  a Low pressure system just north of Lake Winnipeg.   Accumulations are expected to be minor.

Manitoba

Much of central Manitoba will see snow today, from the northern Interlake toward Thompson.    A weak Low pressure system will feed the moisture into some rather cool air.   Manitoba won’t enjoy the warmth experienced by the provinces to the west as temperatures across Manitoba will fail to get much above -10.

 

Friday:

Alberta

Very mild weather in the Pacific flow, and double digit high temperatures are expected along the foothills, east to Drumheller, and north to the Peace Region.   Further east and north of that very warm zone, temperatures elsewhere in Alberta will climb above zero, with a west to southwesterly wind, which could be brisk near the higher terrain.  No significant precipitation is expected anywhere in Alberta.

 

Saskatchewan

It’s in northern Saskatchewan where the mild pacific air collides with colder air, producing snow for the far northeastern corner of the province, and a band of freezing rain or mixed precipitation where the two air masses meet.   The band of dangerous freezing precipitation will extend from about Meadow Lake southeast to Moosomin or Balgonie.   There are likely to be travel issues, and weather warnings should be monitored closely.   Dry, breezy, and safe weather will continue through the day in southern Saskatchewan.

 

Manitoba

High pressure in northern Manitoba will maintain dry conditions across the province in the morning.   However, that high slips southeastward into Ontario, allowing moisture to arrive from northeastern Saskatchewan.   For Manitoba, snow will fall from the interlake up to the northwestern corner of the province by afternoon.  There is a chance of a mix of rain and snow north of Brandon.    From the interlake south, temperatures will peak near zero, with much colder weather, as low as the -20s, expected in northern Manitoba.

 

 

 

Saturday:

Alberta

The weather pattern of warm air and westerly wind begins to break down.  A Low pressure system will develop later in the day in southern Alberta.   The low, in eastern Alberta south of Oyen, will become an Alberta clipper, moving rapidly eastward, spreading rain or freezing rain to the north, from Edmonton to the northern edge of Jasper National Park.  By midnight, the precipitation will intensify as the centre of the clipper moves into Saskatchewan.  Expect snow, rain, freezing rain through central Alberta in the evening, with potential disruptions to travel.   Be aware of weather warnings.   On the south side of the system, it will be warm, as temperatures could reach double digits south of Calgary.

Saskatchewan

The day begins with peaceful weather, but as an Alberta clipper moves into the province in the afternoon, things will turn nasty.   Temperatures will climb above zero in the southern 2/3rds of the province.   The incoming low pressure system and mild weather will lead to a significant band of freezing rain across south central Saskatchewan in the evening.     These are dangerous travel conditions, and weather warnings are expected.    The band of freezing rain should remain north of Regina, but any slight change in the weather pattern could bring it farther south.   Up to date forecasts should be consulted all across southern Saskatchewan Saturday.

Manitoba

It will be another mild day across most of Manitoba, with temperatures rising above the melting point as far north as Leaf Rapids.   Scattered snowflurries are possible in northern Manitoba.  The mild air is coming in from the west, ahead of the Alberta clipper that brings rain, snow, and freezing rain to Saskatchewan.   The inclement weather noses into western Manitoba late in the evening, with a mix of rain and snow developing north of Brandon.

Sunday:

Alberta

There won’t be much change in the temperature throughout the day.   On the back side of Saturday’s clipper, there will be a strong northerly wind, and while temperatures will be steady near zero across the southern 2/3rds of the province, expect the wind to make it feel much colder.   And throughout the day, snow will fall in central and eastern Alberta.  The strong wind will likely creating blowing snow conditions that will impair travel in many areas, including the QE2 between Red Deer and Edmonton.

Saskatchewan

Snowstorm!  Temperatures near zero in the south, cooler north of the Trans Canada Highway.   Heavy snow is likely, as the Low centres itself between Regina and Saskatoon.   This Low, an Alberta clipper, has  a tight pressure gradient, which will generate a strong wind.   Blowing and drifting snow are likely.   Travel will be disrupted.   The duration of the storm, though, will be short.   Ablerta clippers move fast, and by the late afternoon, the most disruptive weather will move on to Manitoba.

Manitoba

It will be mild, especially south of the Trans Canada highway.   It will also become stormy in the afternoon, as the Saskatchewan Low moves to Manitoba.   By sunset, the Low will end up near Portage,  To the north of the Low, expect heavy snow in the interlake.   South of the low, snow will develop, but not until later in the day, perhaps evening.   There will be a strong wind, and visibility will be reduced in blowing snow.  Travel conditions in southern Manitoba will deteriorate as the day goes on.

 

 

COMPARE TO LAST WEEK: Prairie Weather This Week – Nov 25