Some nice weather is on tap for Southern MB over the next couple of days as Mother Nature gives us some late summer weather before the official start of fall on Monday. Thursday will see brisk southerly winds of 40 to 60 km/h developing in the Red River valley as a warm front moves through southern MB. Afternoon temperatures will climb into the 24-27C range along with plenty of sunshine. Friday will see a weak cool front push through from the Interlake, but temperatures should remain above normal Friday with highs of 25C or so before cooling off in the afternoon or evening as northerly winds develop. Saturday will likely see cooler temperatures as we get northeast outflow winds from a cool high pressure area over northern MB. Current advertised highs of 25C are likely over-optimistic for Saturday, with highs of 17-20c more likely in the cooler airmass. There could also be considerable cloudiness around along with areas of dense fog as that frontal boundary remains stalled over southern MB separating warm air to our south from cooler air to the north. (in fact, Saturday's weather may be much like today's.. overcast and cool) By Sunday we should be getting back into south or southeast winds which would boost temperatures back into the low to mid 20s (current advertised high of 27C still likely about 5c too high for Winnipeg and areas to the north and east) So although the bulk of the weekend is expected to remain dry, I don't think it's going to be as warm or as sunny as current forecasts indicate.
Fall officially arrives at 10:44 am Monday morning but current models are suggesting we'll be staying with above normal temperatures in the low to mid 20s through Tuesday before more fall-like temperatures return by mid to late week.