We’ve seen a fairly active weather pattern over the last couple of weeks across the Prairies, but the weather models have done a pretty good job with the medium range forecast.
The biggest miss of last week’s forecast was the intensity of heat that moved into southern Saskatchewan. The forecast had called for a ridge of high pressure to build across that region, which would bring warm temperatures, but it failed to forecast temperatures in the low and mid thirties.
To start this forecast period, we have an area of low pressure developing over Montana. This will help bring one more day of intense heat over southern Saskatchewan and a hot day over Manitoba. That same low will bring partly cloudy skies and the chance of showers to a good portion of Alberta.
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The low is forecasted to lift northwards into north-central Saskatchewan on Thursday before slowly drifting off to the east to be situated in northwestern Ontario by Saturday.
A northwesterly flow behind this low will bring cooler temperatures right across the Prairies over the weekend.
Once this low is out of the picture, the weather models show an a large area of high pressure building into the Prairies. This high looks to dominate the weather for much of next week and possibly into the Labour Day long weekend. Expect sunny skies and warming temperatures with daytime highs pushing into the mid to upper twenties by mid week.
The upper twenties to low thirties not out of the question later in the week. So those of you hoping for one more hot summer week you might just get it!
Alberta
A short and straight forward forecast. An area of low pressure over Montana with a trough extending northwestwards into Alberta will bring a mix of sun and clouds on Wednesday. It will also bring a chance of some showers with the moderate risk of some severe thunderstorms over central regions.
As the Montana low lifts northwards into central Saskatchewan on Thursday, skies will clear as high pressure builds into the region. Circulation around the building high and the departing low will pull cooler air southwards with daytime highs forecasted to be in the 20 C range. Overnight lows are expected to fall to around 8 C.
High pressure looks to dominate the weather for the remainder of the forecast period. This should bring sunny skies and warming temperatures. A large area of high pressure will settle across the Prairies with the center of the high forecasted to be over the eastern Prairies by Monday. This will place Alberta in a southerly flow, which will help boost daytime highs into the mid to upper twenties by Wednesday with overnight lows warming into the low to mid teens.
Saskatchewan and Manitoba
Warm to hot temperatures are on tap for Wednesday across both provinces as warm air is pulled northwards ahead of an area of low pressure developing over Montana. Expect daytime highs over southern Saskatchewan to be in the low to even mid thirties. Manitoba and central Saskatchewan should see highs in the upper twenties to low thirties.
The Montana low is forecasted to lift northwards overnight Wednesday and into Thursday morning to be positioned over north-central Saskatchewan. The instability from this low, combined with the heat and humidity will bring a high risk of severe thunderstorms to southeastern Saskatchewan and western Manitoba.
The weather models are showing the low slowly drifting east or southeastwards on Friday and Saturday. This will bring a mix of sun and clouds to southern regions along with the slightly chance of some showers or thundershowers. Over central regions, skies will be mostly cloudy with a good chance of showers and thundershowers along with the risk of some thunderstorms.
The clouds, precipitation and instability should move east of the Prairies by Sunday. Temperatures will be on the cool side as cooler air is pulled southwards behind this low. Expect daytime highs to be in the upper teens to low twenties with overnight lows in the 10 to 12 C range.
High pressure is then forecasted to begin building in and bringing what looks to be an extended period of sunny skies and warm temperatures. The high is forecasted to drop southeastwards on Monday to be centered around southern Manitoba. This high is currently forecasted to stall out over Manitoba for a couple of day before drifting to the southeast.
Temperatures on Monday will start off seasonable with daytime highs in the low twenties, but with the sunshine temperatures will warm a little bit each day with highs by Wednesday forecasted to be in the mid twenties. Looking further ahead towards the long weekend, the weather models are showing daytime highs warming into the mid to upper twenties as upper ridging builds across the Prairies. As usual, that is a long way off and plenty can change by then.
