This forecast period looks to be be defined by two areas of low pressure, one spinning off the west coast and the other spinning over eastern Canada. Exactly how these two lows behave a move will have a big impact on temperatures across the central and eastern Prairies.
We start this forecast period with a strong Colorado low headed northeastwards into northwestern Ontario. This low will likely only brush southern Manitoba, but once it passes it will allow cooler Arctic air to build southwards across the eastern Prairies. To the west, there’s a deep area of low pressure pushing into the Gulf of Alaska, which is forecasted to spin offshore for most of this forecast period. This will allow for an upper ridge to build over B.C. and Alberta by the weekend.
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For this forecast period we are starting off with a large area of high pressure over Ontario and an equally large area of low pressure over the Yukon. The clockwise flow around the Ontario high, combined with the counterclockwise flow around the Yukon low, is creating a widespread southerly flow across the Prairies. This should lead to one more day of warm temperatures across the western Prairies and a couple more days over the eastern half.
As we head into next week, the weather models show the eastern trough of low pressure staying mostly in place. This will keep the warm temperatures associated with the western ridge confined mostly to Alberta and maybe Saskatchewan, depending on exactly how the Ontario trough behaves.
Alberta
A weak area of low pressure over northeastern Alberta, combined with an approaching warm front from the Pacific, will bring a mix of sun and clouds to most regions. This will come with the chance of a few showers or flurries, depending on the time of day. Unstable conditions over southern regions could bring some heavier areas of snow. Expect daytime highs to be a few degrees on either side of the freezing mark with overnight lows falling to around -7 C.
Spring or even summer-like temperatures are forecasted to move in by Sunday or Monday as a sharp upper ridge builds ahead of a deep area of low pressure in the Gulf of Alaska. This ridge will bring mostly sunny skies and very warm temperatures. Daytime highs are expected to be in the low twenties across southern regions with upper teens to around twenty degrees expected over central areas. These mild temperatures look to stick around to about mid-week when the upper ridge is forecasted to collapse, which will allow colder air to move back in.
Saskatchewan and Manitoba
Two areas of low pressure will impact these regions on Wednesday and Thursday. The first low is over northern Saskatchewan, which will bring clouds and some flurries to central and northern Saskatchewan on Wednesday. The second low is forecasted to clip southern Manitoba overnight Wednesday and into Thursday morning. It should bring scattered showers or periods of lights snow to south-central and eastern regions. Amounts from this system look to be fairly light with far eastern regions possibly seeing 5 cm of snow. Winds will be quite blustery from the north as the low passes by.
Cool Arctic high pressure is forecasted to build southwards behind this and while it will bring clearing slides, expect daytime highs to be only around the freezing mark. The biggest area of uncertainty is over far wester Saskatchewan as to exactly how far east the upper ridge and resulting mild air will be able to push.
As we move into Monday and Tuesday, it appears that the western upper ridge will push eastwards and collapse. As it collapses it will still bring milder air to both provinces with daytime highs forecasted to push to around the 10 C mark with slight cooler temperatures expected over regions that still have snow cover.
