Slightly cooler weather will move in this weekend behind a low pressure system forecast to move through tonight and tomorrow. In addition to the cooler temperatures, this system will bring a chance of rain and thunderstorms to the Red River Valley.

Tonight & Tomorrow

Friday

27°C / 18°C
Increasingly cloudy; risk of a thunderstorm late in the afternoon into the evening. Humid.

We’ll see gradually increasing cloud today as the surface trough associated with a low pressure system pushing into the northern Interlake approaches. There may be some ongoing thunderstorm activity along the trough this morning as it pushes through SW Manitoba and that threat will move eastwards into the Red River Valley by the late afternoon or early evening. A southerly wind ahead of the trough coupled with a capping inversion will draw moisture northwards once again and trap it near the surface, making for another hot, sticky day here in Winnipeg. Our high temperature will only climb to around 27 or 28°C, though, thanks to the increasing cloudiness through the day. That hot, humid weather will bring the threat for thunderstorms – potentially severe – late in the afternoon into the evening hours. At this point, it seems like somewhere between 8PM and 11PM seems like the most likely time for seeing any potential storm activity. After that we’ll see our temperature drop to around 18°C under a partly cloudy sky.

Saturday

25°C / 12°C
Becoming cloudy, good chance of showers or thundershowers. Humid again.

Saturday will be another humid day as we remain in the moist air mass ahead of the cold front. We’ll see a fairly good chance of showers or thundershowers beginning later in the morning and through the afternoon. Skies will start off as a mix of sun and cloud but should become fairly cloudy in the afternoon as things become more unstable with the approaching cold front. We’ll see a high of around 25°C which will mark the last day in our hot, muggy air mass. The threat for showers or thunderstorms will persist until the cold front passes.

The cold front will push through overnight, bringing northwesterly winds that will clear out much of the moisture and drop us to a comparatively cool 12°C for an overnight low with clearing skies.

Sunday & Holiday Monday

Sunday

23°C / 8°C
Sunny. Cooler and much less humid.

Monday

25°C / 13°C
Sunny and warm.

Sunday and Labour Day Monday look absolutely beautiful. Sunday will be slightly cool with a high of only around 23°C and lead into a chilly night with a low dropping into the single digits bottoming out around 8°C. The heat starts to return on Monday with sunny skies continuing as we climb to a mild 25°C.

The Trend Next Week

Looking further into the week, it looks fairly nice overall as the upper ridge begins rebounding back northwards into the Prairies. Highs will push back into the upper 20’s with humidity staying fairly low until late in the week. Things look fairly dry through the first half of the week, with a few weak disturbances bringing the threat for isolated-to-scattered thunderstorms late in the week. For the most part, though, it looks to be a beautiful, warm week. Summer may be late, but it doesn’t look like it’s going anywhere soon!