Prairie Weather (Rural Roots Canada) – Soil moisture’s low – will midweek storms help?

 

Stormy weather is ahead this week for central Alberta, south-central Saskatchewan and southern Manitoba.   As usual, the moisture will be welcome and beneficial, with many areas continuing to show soil moisture deficits.   In southwestern Saskatchewan, there are reports many farmers have given up on the season,  and four municipalities, Maple Creek, Fox Valley, Enterprise, and Waverly have declared states of emergency due to drought.  Fortunately, conditions elsewhere on the prairies aren’t as dire.  Below is the latest soil moisture map from the government of Saskatchewan.   It shows southwestern Saskatchewan, west of Moose Jaw,  is indeed in trouble from a lack of moisture, but most of the rest of the province’s agriculture region is faring much better.

According to the Saskatchewan crop report, across the province, half of fall and spring cereal crops are in good condition, with the other half in fair to poor condition.   Half to two thirds of pulse crops are in good condition.  Most livestock producers have started their first cut of hay this year, as crops are headed toward maturity at a faster than normal pace.  As mentioned, conditions are poorest in the southwestern part of Saskatchewan due to dry weather, heat, and wind, which has led to further damage from grasshoppers and flea beetles.

For comparison, here is the soil moisture chart from the Manitoba Crop Report.   Most of the map is shaded yellow, indicating Optimal soil moisture conditions:

Courtesy: Manitoba Crop ReportCereal crops in Manitoba are doing well, with a majority in good condition.   None are considered to be in poor condition.   The interlake region is doing very well, where 60 percent of cereal crops are in excellent condition.

And in Alberta, beneficial rainfall over the past couple of weeks has brought soil moisture levels up, especially in central and southern regions.   North of Edmonton, it remains dry:

 

The map above shows soil moisture departure, which means the difference between long term normals and actual soil moisture measurements.  Central Alberta, and the middle portion of the south zone is doing well, with an excess of soil moisture.   61 percent of all crops across Alberta are in good to excellent condition.   Across Alberta, crops are flowering early, ahead of the 5 and 10 year averages.

 

So…what can we expect this week?  This question is more difficult than usual to answer.   That’s because much of this week’s precipitation will come in the form of thunderstorms, which will occur along with the passage of a cold front during the mid week.    Thunderstorms are randomly scattered, and while one area may receive a lot of rain, a neighbor on the next grid road may get nothing at all.

The map below shows abundant rainfall this week for the southern prairies, with two exceptions.   There’s not much rain on the way for the parched prairie of southwestern Saskatchewan, and southeastern Saskatchewan receives less than 10 mm of rain.  Northern parts of Alberta and Saskatchewan may also receive significant rainfall.

Courtesy: ECCC

Here’s what to expect this week:

 

Monday

Alberta

A surface high centered over the continental divide will keep Alberta under a mainly sunny sky.  No significant precipitation is expected, and the wind will be light and variable.  A strong weather system off the BC coast may shoot some cloud into the Jasper area late in the day, and scattered afternoon showers are possible in the northern forest.  Agricultural regions will remain dry, and this is a good opportunity to get some outdoor work done, as rain will come along later in the week.  Across the province, high temperatures will reach the mid twenties, with a chance to reach the low 30s east of Highway 2, and south of the Trans Canada Highway.

Saskatchewan

During the day Monday, a surface Low pressure system will move slowly from Saskatoon to Moosomin.  There is a chance for significant rainfall along that track, along with some thunderstorms.  It’s not a particularly strong Low, but it is tightly wound, so expect considerable wind along with the rain.  Unfortunately, the rain won’t reach as far west as the desperately dry regions of southwest. Here’s the HRDPS model depiction of the disturbance from 6 AM to 6 PM Monday:

 

The rain will keep southeastern Saskatchewan cool, with highs only in the mid teens.  Elsewhere, temperatures across Saskatchewan should reach the low to mid twenties.

Manitoba

As the map above shows, southern Manitoba can expect some rain or showers on Monday.  As the Low moves toward Manitoba from saskatchewan, it will weaken, so rainfall amounts will be light.  That said, there could be enough instabillity to trigger some thundershowers north of Brandon, and, later in the day, in southern Manitoba south of the Trans Canada highway.    Because the north will get a lot more sun than the south, there is the rare chance for the hottest weather in Manitoba on Monday to occur along the Hudson Bay shore.   Because of the rain in the south, temperatures in that region may remain below 20 degrees.

 

Tuesday

Alberta

Tuesday will be another uneventful day in Alberta.  The southern half of the province will experience sunshine, with cloudier conditions prevalent in the north.    Where sun meets cloud sits a weak low pressure system spawned from a much larger disturbance on the BC Coast.   There could be some showers or thunderstorms near the low during the afternoon, somewhere in the area from Entwistle to Edson.  The BC coastal disturbance will move inland, and will shape prairie weather in the days to come.

Tuesday will be hot in Alberta, with temperatures reaching 30 in the Medicine Hat area by noon.    In the afternoon, the heat spreads, and most areas east of Highway 2 will reach 30 or higher during the afternoon.   It will be cooler, but not by much, in the rest of the province, with highs between 25 and 30.

Saskatchewan

Tuesday will also be a quiet day in Saskatchewan.   Rain is not expected, and most regions will see bright sunshine through the day.  The wind will come out of the south.   The bad news – southwestern Saskatchewan, the driest region of the province, will be the hottest part of the province with highs in the low 30s.  Most of the rest of the province will reach the 25 to 30 degree range, though it may be a few degrees cooler near the Manitoba boundary.

Manitoba

A few early morning showers are possible in western Manitoba, otherwise, the province will spend the day under a blue sky, with no significant weather.   Just as Monday, temperatures will be higher in the north (25-30), than in the south, (20-25).

 

Wednesday

Alberta

While most of the hot air from Tuesday moves into Saskatchewan, southeastern Alberta will once again reach the 30s.  In a line from Calgary to Lloydminster, highs will reach the high 20s, and to the north and west of that line it will be cooler.   That cooler weather is due to a southwest-northeast band of rain that will develop early in the day, and intensify as it moves north.

A second area of showers will develop as a low pressure system forms in southern Alberta, near Gleichen. The low will generate afternoon showers and storms in south central Alberta, centered on Calgary.   South of High River, it should remain dry.

A hot and humid air mass will settle over central Alberta, and if storms develop in that area, they could turn severe, with heavy rain, hail, strong wind, and the potential for isolated tornadoes.

Saskatchewan

South Central Saskatchewan will find itself in the same hot, humid air mass that reaches Alberta.  And the consequences could be similar with the potential for severe storms, and all they entail.  This includes the possibility of hail and isolated tornadoes.   There is a lot of uncertainty at play, and there is a chance that while hot and humid, storms will not be triggered, and it will be nothing more than a muggy day.   Most locations in the southern 2/3rds of Saskatchewan will swelter, with highs in the low 30s.  Not far away, just to the south,  afternoon highs in northeastern Montana could reach the 35-40 range.  And, there’s a chance of severe storms there, too.

Manitoba

In Manitoba,  Wednesday will be another uneventful, sunny day with a light south wind.   Along the Saskatchewan boundary, highs will reach the 30s, but most of the province will be spared the extreme heat and humidity that will dominate in Saskatchewan.    That said, it will still be quite warm, with highs between 25 and 30.

 

Thursday

Stormy weather continues across the prairies Thursday, with a focus on southeastern Manitoba, where severe storms are likely.  The map below shows a widespread threat of thunderstorms across the agricultural prairies Thursday, but in the vast majority of areas, that threat is minor.    Note that the map shows where storms could erupt, not necessarily where they will erupt.

 

Alberta

It will be a wet day south of Red Deer, with rain, showers, and thundershowers through the day.   The area of rain will span the south from SE BC to the Saskatchewan boundary, and well beyond.  Rainfall could be heavy, especially where tbundershowers break out.  The likelihood of severe storms is not as great as Wednesday, but they can’t be ruled out, either.   The map below shows expected rainfall amounts on Thursday:

 

Because of the wet weather, and the passage of a cold front, it will be cooler in Alberta on Thursday, especially in the south.  Across Alberta, expect highs between 15 and 20 degrees, depending on the timing of the rainfall.  It will be warmer in southeastern Alberta, with highs in the mid 20s.

 

Saskatchewan

As the map above shows, southern Saskatchewan should  get some measurable rain.    In the rain, temperatures are likely to remain below 15 degrees.   Southwestern Saskatchewan will get measurable rain,  but nowhere near enough to make a dent in the drought.  The rain in southwestern Saskatchewan will peak in the late afternoon, and taper off as it moves east across southern Saskatchewan.  Overnight into Friday morning, it should taper off entirely. There is a severe thunderstorm threat Thursday, especially across southern Saskatchewan along the Trans Canada Highway.

Manitoba

Conditions are setting up for showers, thunderstorms, and severe weather Thursday in southern and eastern Manitoba.

Through the afternoon, heat and humidity will build across the region, creating an unstable atmosphere. Two weather systems capable of triggering severe storms  will move through.  First, there will be a warm trough east of Lake Winnipeg and into the Red River Valley this afternoon, and then a stronger cold front pushing through in this evening.

For most of the afternoon, a “cap” of warm air higher up in the atmosphere should keep thunderstorms from developing. However, there’s still a small chance of isolated storms popping up. If one does form, it could quickly turn severe with the potential for torrential downpours and large hail.

In the evening and overnight, the risk of storms increases. The advancing cold front, combined with upper-level winds from the Dakotas, could trigger a line of scattered thunderstorms overnight and into Friday morning. Some of these storms could be strong or severe initially, but as they spread out and become more widespread, the risk of damaging weather should ease.

Friday

Alberta

Quiet weather returns to Alberta on Friday, with sunshine in the south, and clouds to the north.   Significant precipitation is not expected.   It will be warmer again, with highs in the mid 20s across most of the province.  Highs between 25 and 30 can be expected in southeastern Alberta.

Saskatchewan

Severe weather is not expected, but there is a good chance of rain moving southeast from Saskatoon to the Moosomin Balgonie area in the afternoon.   Significant accumulations are unlikely.  The rain will limit temperatures in that area to the 15 to 20 degree range, while in the rest of the province, temperatures could climb to the mid to high 20s.

Manitoba

A low pressure system over south central Manitoba will generate a day’s worth of rain across the southern part of the province.   Thunderstorms and severe weather are again possible.   The heaviest rain will likely occur in western Manitoba near Carberry. The map below shows precipitation accumulation between midnight Friday morning, and midnight Saturday morning:

Because of the wet weather, highs across southern Manitoba will reach the low 20s at best.

 

Saturday

Alberta

While rain will fall in the forests of northeastern Alberta, agricultural regions across the province will remain dry, and no significant weather is expected.  A Low pressure system in the Pacific off the BC coast will push a west to northwest wind across the province.  In the northern 2/3rds of the province, highs will reach the mid 20s.   In southern Alberta, it will warm to the 25 to 30 degree range, exceeding 30 degrees south of highway 3 between Lethbridge and Medicine Hat.

Saskatchewan

Similar to Alberta, there will be rain in Saskatchewan Saturday, but most of it will be in the forested northern regions.   In the afternoon, though, some of that rain may venture as far south as the Saskatoon area, providing rain to central Saskatchewan fields and pastures.   However, amounts will be disappointingly minimal.  In southern agricultural regions, highs will range between 25 and 30 degrees.   Highs in the low to mid twenties can be expected in the rest of the province.

Manitoba

Early in the morning, expect rain from Portage La Prairie east into Ontario.  By afternoon, the rain tapers off west of Winnipeg, but continues through the day east of the Red River Valley.  Afternoon thunderstorms will be possible in the area.  Because of the rain, temperatures in southern Manitoba will be limted to the low 20s.   HIghs in the mid twenties are forecast for central and northern Manitoba.

Sunday

Alberta

Rain returns to Alberta on Sunday,  developing in the morning in central and northern regions.   In the afternoon, the rain will move southward, and spread across parts of southern Alberta, where it will intensify into the evening and overnight.  By midnight, rain will be falling all across central and south central Alberta, and along the foothills north, almost all the way to Grande Prairie.  The Bonnyville/Cold Lake area will receive heavier rainfall in the afternoon and evening.  Some of the forecast models are suggesting hot weather with highs in the 30s for southern Alberta.   These temperatures will be acheived in the early to mid afternoon before the rain arrives and intensifies.

Saskatchewan

A Low pressure system will provide rain early in the day to the northern forests, before moving southward in the afternoon.   That southward turn will bring rain to central and southern Saskatchewan in the afternoon, and into southern Saskatchewan by evening.  Thunderstorms can’t be ruled out.

Manitoba

While rain falls in central Manitoba, the agricultural south will stay dry all day, with plenty of sunshine.   Warm weather returns to the area as temperatures in the south climb to the 25 to 30 degree range.  In the north, highs will peak between 20 and 25 degrees.

 

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