Prairie Weather (Rural Roots Canada) –  As December begins, prairie weather warms up, but not for long.

Frost and fog have characterized recent mornings across much of the prairies over the past few days.  The frost decorates the trees, and ices up the ground last Saturday morning near Ryley, Alberta:

Photo: Linda HuntHigh pressure has kept the sky mainly clear for the past few mornings, allowing the frost and fog to form.    This is expected to change, as a turn to milder weather begins Monday, along with the return of snow and freezing rain.

As of November 30th, most of southern Manitoba had yet to receive a measurable snowfall accumulation.   There is snow on the ground, though, in most of Alberta and much of Saskatchewan,  thanks to some snowy weather through November.  The map below shows departures from average precipitation.   The brownish colours show where November was drier than average.   The  bluish colours show areas that received higher than average precipitation:

 

Courtesy: Agriculture and Agri-Food CanadaHere are some November snowfall accumulation totals for the month of November, from the CoCoRaHS network of volunteer weather observers:

November Snowfall Accumulations in Alberta

Monday

Alberta

The day begins with a mainly clear sky, which leads to the possibility again of early morning fog and frost.   An upper ridge of high pressure will dominate, but at the surface, a low in the southern Yukon will move southeast, and by midday, there will be snow in northern Alberta, with a chance of freezing rain in the mountains and foothills from Jasper northwest through the Peace region and into northern BC.    By late afternoon, the low moves into northern Alberta, where the snow becomes more widespread, and the freezing rain continues over higher elevations.   South of Edmonton, it should remain dry, and west of Highway 2, it’s expected to remain mainly sunny.  It will be warm across much of the province, with highs of 0 to 5 degrees from the Peace region south to the US border.   In northern and northeastern Alberta, highs will range from -5 to -15.

Saskatchewan

No significant weather is expected in Saskatchewan Monday.   Most of the province will be under a mainly sunny sky,  with a light to moderate westerly wind.   However,  Saskatchewan won’t be able to share in Alberta’s warmth, except for the southwestern corner, where highs will range from 0 to -5.   East of Moose Jaw, and across the rest of the province, it will remain cold, with highs in the south between -5 and -10, and to the north, -10 to -20.

Manitoba

It’s another seasonably cold forecast for Manitoba on Monday, with highs in the -10 to -15 degree range.  Those in the far north of Manitoba, can expect temperatures closer to -30 (not a typo).   Other than light snow around the northern basin of Lake Winnipeg, it will be an uneventful weather day in Manitoba.   No significant precipitation is expected.

 

Tuesday

Alberta

The upper ridge breaks down, and a northerly flow establishes aloft.   Snow will develop across the Peace Region, and through central  and southern Alberta. High pressure to the northeast is likely to create an upslope flow against the foothills and mountains, enhancing the snowfall in those regions.  Travel may be impacted in central Alberta, due to blowing snow caused by a brisk north wind.  Despite the snow, it will be relatively warm, especially near the foothills with highs between 0 and -5.  Elsewhwere, highs will range from -5 to -10.    Snowfall amounts will be relatively minor.   The map below shows the 24 hour snow accumulation by midnight Wednesday morning.

 

 

Saskatchewan

A surface low pressure system moves from central Alberta into southern Saskatchewan during the early morning, then into Manitoba by midday.   Snow will fall along the travel path of the Low, covering much of central and southern Saskatchewan.   In addition, there will be a brisk north wind, and it could be quite blustery.  There may be difficulties in travelling through the area as the stormy weather rolls through.  That said, it won’t be super cold.  Expect some fairly warm weather south of Saskatoon, with highs near -5.  To the north, it will be much colder, as temperatures remain close to -15.

Manitoba

A cold front rolls through central and southern Manitoba Tuesday, bringing snow to the southern half of the province.    The snow will last through the day, but because the snow will be light, and the front will move through rather quickly, snow accumulations will be under 5 cm.  The sky will clear out in the evening, after the snow and the cold front have passed through.   The northern half of the province will miss out on all this, and should stay mainly sunny.   The clearing sky will lead into a cold night, with overnight lows between -15 and -25.

 

Wednesday

Alberta

A ridge of high pressure in the Pacific keeps a northerly upper flow over Alberta.   Embedded in that flow is another low, which will bring more snow to northern  and central Alberta on Wednesday.  Southern Alberta should stay dry.  Southeast of Calgary there will be a partly cloudy sky.  Again, snow amounts will be light – less than 5 cm, with no significant snow anticipated south of Highway 9.   It will be a warm day, with highs near 0 in southern and central Alberta, and as far northwest as the Peace region.   Outside of these areas, expect highs from -5 to -10.

Saskatchewan

A high pressure system over Saskatchewan will keep the sky clear across the province until the late afternoon.  That’s when a Low drops down from the north, and spreads snow across the northern third of the province.   This is nowhere near any agricultural land.   Even as the snow arrives in the north, the southern half of the province will remain under a clear sky going into the early evening.  Overnight, some of the snow may then slump southward as far as the Trans Canada Highway.   It will be a cold day across Saskatchewan, with highs in the -15 to -20 degree range.

Manitoba

Highs of -15 in the south and -25 in the north,  and most of the province will be under sunshine through most of the day.   No significant weather is expected for Manitoba Wednesday.

 

Thursday

Alberta

It will be an extraordinarily warm December day in Alberta on Thursday.   From the Peace region south to the US border, highs will exceed the melting point, as a broad chinook sets up.   Most of the south will see a combination of chinook cloud and sunshine.   Yet again, though, there is a disturbance that will be guided by the upper level flow, moving from the northwest to the southeast,  starting in the Peace region, ending up near Lloydminster.   Snow will fall along and north of that track.   The map below shows accumulations of 3-10 cm in that swath of snow:

 

 

Saskatchewan

A low pressure system moving through the province from the north to the southeast will bring more snow to Saskatchewan Wednesday.  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 on Thursday:

 

 

The low is also going to bring some cold weather to the province on Wednesday.  Most areas will remain colder than -15.

Manitoba

As shown on the map above, central and southern Manitoba can also expect a minimal amount of snow on Thursday, 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 places to the north, highs will be in the =15 to -20 degree range.

 

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.   Here is the temperature outlook for midnight Friday morning.   Temperatures will be above the melting point in southern Alberta and southwestern Saskatchewan, and will be comparatively mild elsewhere across the prairies:

 

And, here are the expected temperatures in the mid-afternoon:

 

Colder air has come down from the north, and while it’s by no means bitterly cold, it does signal a change in the weather pattern.   A change that will bring more snow to most of Alberta and western Saskatchewan, and a few flurries to Manitoba.   While it’s impossible to accurately predict snow totals more than 48 hours in advance, it’s fair to suggest Alberta will get the heaviest of the snow, and it may cause disruption to travel.   It may be a day to check out 511alberta for road conditions and Environment Canada for weather updates before heading out.    In Saskatchewan, road conditions can be found at Highway Hotline, and in Manitoba, consult Manitoba511.

 

Saturday and Sunday

Temperatures will rebound in Alberta on the weekend, with highs above the melting point along the foothills Saturday,  with the warmth expanding east on Sunday.    Saturday in Alberta will be mainly cloudy, and Sunday will become sunny areas west of highway 2, and along highway 3 between the Rockies and Saskatchewan.   Another NW to SE band of snow will set up over central Alberta Saturday, but by Sunday, the only snow in the province will be in the north.    Meantime, high pressure over Saskatchewan and Manitoba will keep those provinces dry under a mainly sunny sky.   Very cold weather is expected Saturday morning, with lows near -30 in and near Saskatoon.  It will be much colder than average in Manitoba as well on Saturday.   Sunday – Saskatchewan gets warmer, while Manitoba’s temperatures drop.    We’ll be able to provide more specific detail in the Midweek Update on Thursday here at Rural Roots Canada.