Prairie Weather (Rural Roots Canada) – Weekend weather flips. In Alberta, Saturday’s hot, Sunday’s not. Saskatchewan sizzles, and Manitoba’s cool
A weak upper ridge holds over western Canada, with a system exiting into Manitoba clearing the way for a few days of sunshine and warming temperatures across the west and central Prairies. That calm doesn’t last the whole period. A low develops over south-central Alberta by the weekend, bringing renewed clouds, showers, and thunderstorms to much of Alberta by Sunday before pulling warm air north into Saskatchewan and Manitoba and setting up a growing thunderstorm chance heading into next week.
The latest Canadian Drought Monitor indicates a return to abnormally dry or drought conditions in parts of the prairies and the BC Peace Region.
Most agricultural areas across the Prairies remain in reasonable shape. Growing-season precipitation is running 90 to 150% of normal, and east-central Alberta, along with southwestern Manitoba and east-central Saskatchewan sitting well above normal, over 150% in spots. Two areas stand out as genuine concerns, though. The Peace region in Alberta and BC has run near-to-below-normal precipitation all growing season and continues to worsen. The BC side is now showing reduced yield expectations in parts of the Peace and around Vanderhoof. And across the southern Prairies, recent dryness and above-normal heat, 3 to 5 degrees above normal in southern Alberta and southern Saskatchewan in July, have pushed Abnormally Dry conditions into the corridor between Red Deer and Calgary and along stretches of the southern border. Further north, Severe to Extreme Drought has expanded across northern Alberta and the area north of La Ronge in Saskatchewan.
As shown in the map below, significant rainfall is not expected across the agricultural regions of the prairies from now until Sunday night. The moisture indicated is mainly due to the Sunday event mentioned above. Until then, dry weather dominates.
Thursday
Here is the thunderstorm outlook for Thursday. The most significant threat will be parallel to the Alberta foothills:
Peace Region
Warm and dry weather continues over the Peace Region Thursday, part of a warming trend that will see hot weather return later in the week. Thunderstorms are possible on the Alberta side, less likely in the BC Peace. Temperatures will reach the mid-20s in the afternoon.
Alberta
Thermal troughing sets up along the foothills and as far east as Gleichen and Lethbridge Thursday, bringing a real risk of severe hail. Instability is modest, but there still may be enough energy to support supercell development, and low freezing levels favour large hail. A shortwave crossing the southern foothills late in the afternoon could act as a trigger for strong storms. Separately, a shortwave swinging through Cold Lake and Fort McMurray brings another round of thunderstorm potential, with enough shear for multicells and a small chance of brief rotation producing isolated severe weather. Highs across Alberta will be in the mid-20s, reaching the high 2os in the far south.
Saskatchewan
Smoky skies are possible in the southeast late in the afternoon as westerly flow pushes smoke in from southern BC fires. Thunderstorms are possible over north-central and east-central Saskatchewan this afternoon and evening, tied to a surface trough and an associated cold front, though these should stay weak. Given how badly the area north of La Ronge needs rain after returning to Extreme Drought conditions, weak storms like these won’t move the needle much, but any rain that does fall is still a net positive. Harvest activity in the southwest continues at a modest pace, with the province’s last report showing progress holding at 2% complete; cooler weather over the past week has slowed things down somewhat but has also helped ease stress on crops still filling. Temperatures in southern Saskatchewan should reach the mid to high 20s.
Manitoba
A low-pressure system, tracking in from east of Great Slave Lake, pushes toward the northern Manitoba boundary today before shifting to a more southeasterly track tonight, bringing periodic scattered showers to northern Manitoba over the next day or so, along with a band of thunderstorms this afternoon and evening. These storms should also stay weak given limited instability. Smoke from NWT fires is expected to move into the northeastern Prairies in the evening, though much of it should stay aloft by the time it reaches most communities. With winter cereal, barley, and pea harvest underway and spring cereals moving through soft-to-hard dough, any rain reaching central or southern parts of the province would be welcome, but today’s activity is mostly a northern story, well away from agricultural concerns. Expect highs in the low 20s across Manitoba Thursday.
Friday
Peace Region
Skies should begin clearing as the ridge builds back in, with warmer temperatures returning. Highs will reach the high 20s or even 30 degrees Friday in the Peace Region. This is a good window to make progress on any harvest or field work that’s been waiting on drier conditions, though the underlying moisture deficit for the season isn’t something a single dry day resolves. And in an area where rain is badly needed, Friday’s weather offers no relief.
Alberta
With the upper ridge remaining in place across the western and central Prairies and surface high pressure settling in, expect plenty of sunshine and warming temperatures, generally into the mid-to-upper 20s. 30 degrees is achievable near the US border. This is a welcome stretch for producers in the Red Deer-to-Calgary corridor now showing Abnormally Dry conditions, at least in terms of getting fieldwork done, even if it doesn’t add any moisture back to the soil.
Saskatchewan
Similar conditions hold, with the ridge bringing sunshine and daytime highs climbing into the mid-to-upper 20s. Good working weather for harvest in the southwest and for any spraying or field work elsewhere in the province. Significant weather is not expected.
Manitoba
Manitoba should stay a little cooler than its neighbours to the west Friday, as cooler air moving in behind the departing trough offsets the warmer air trying to build in. Still, a pleasant, mostly dry day overall, useful for keeping harvest and hay operations moving. Highs will be in the low 20s, with little to no chance of moisture in agricultural areas of southern Manitoba and the Interlake.
Saturday
Peace Region
Continued sunshine and warmth are expected as the ridge holds, the calmest day of the stretch before the weekend system begins organizing to the south. Saturday is the hottest day in the current stretch, with temperatures reaching or exceeding 30 degrees in the Alberta Peace, and climbing to the high 20s on the BC side.
Alberta
The ridge remains dominant through most of the day, with sunny skies and warm temperatures continuing, with some areas reaching or exceeding 30 degrees, as shown on the map below:
Watch the western sky by evening, though, as the low-pressure system expected to develop over south-central Alberta begins taking shape.
Saskatchewan
Sunny, warm conditions continue, rounding out a good multi-day stretch for harvest progress in the southwest ahead of the more active pattern arriving Sunday. As the map above shows, afternoon highs in Saskatchewan on Saturday will be well above average.
Manitoba
Temperatures will try to catch up to the rest of the region today as the cooler air trailing Wednesday’s system finally clears out, leaving a warm, mostly sunny day. That said, afternoon highs will be close to average, and there will be no spectacular heat, as highs remain in the low to mid-20s. In Manitoba, there is potential for afternoon temperatures to exceed the numbers shown on the map above.
Sunday
Peace Region
As a low-pressure system organizes over south-central Alberta, increasing cloud and a chance of showers reach into northern Alberta, likely including the Peace by later in the day. Given the season-long moisture deficit here, this is a system worth rooting for, though it will interrupt fieldwork. And the likelihood of rain means cooler weather, with highs in the low 20s.
Alberta
A developing area of low pressure over south-central Alberta brings increasing clouds and showers Sunday, with thunderstorms becoming possible as the system develops and begins lifting north. The greatest chance of precipitation looks to be across central and northern Alberta, though southern areas could see some showers and thunderstorms. This is a meaningful setup to watch, both for the rain it could bring to dry pockets and for the severe potential that comes with any organizing low this time of year. Most areas of Alberta will cool to afternoon highs in the high teens and low 20s. However, along the US border, south of Highway 3, there is still a chance of hot temperatures in the 30s.
Saskatchewan
Circulation around the Alberta low starts pulling warmer air north into the province Sunday, with increasing clouds and a growing chance of thunderstorms developing late in the day as a frontal wave pushes east ahead of the system. Some of these storms could produce locally heavy rainfall, welcome news for the drought-affected areas in the north. Highs across the southern half of Saskatchewan should reach the low 30s, while the rest of the province climbs into the mid-to-high 20s.
Manitoba
Similar to Saskatchewan, warmer air moves north into Manitoba Sunday, with clouds increasing and thunderstorm chances building through the evening as the frontal wave associated with the Alberta low approaches. Locally, heavy rain is possible with any storm that organizes. Across most of Manitoba, highs Sunday will reach the mid-20s.
