After 4 weeks of mild dry weather over southern Manitoba with virtually no precipitation over that time, it looks like a major pattern change is in store over the Prairies for the last week of October. A strong storm system over the Pacific will be pushing across the Prairies early next week, and will bring rain, strong winds and even the season's first snowfall over parts of southern Manitoba by the middle of next week. Rain ahead of the system is expected to push into the Red River valley Monday afternoon or evening then continue into Tuesday. By Tuesday evening into Wednesday, the storm system is forecast to intensify over northern Minnesota into NW Ontario, bringing strong northerly winds and colder air into southern Manitoba. Temperatures will fall into the low single digits by Wednesday, with rain changing to wet snow over parts of southern Manitoba, especially over higher elevations west of the Red River valley. The colder air will bring an end to the mild weather that has produced double digit highs every day so far this month. Below normal temperatures are expected for the latter part of the week before returning to seasonal values for Halloween weekend.
This storm system will bring the first significant precipitation over the Red River valley in over 4 weeks. Overall precipitation amounts from this system will vary between 10 to 50 mm, with a 50% chance of seeing at least 25 mm of precipitation in Winnipeg between Monday and Thursday. It's too early to say whether we'll be seeing our first snowfall of the season in Winnipeg by Wednesday, but it's likely that the higher elevations of western MB including the Turtle Mountain and Riding Mountain areas will be seeing some accumulating snow from this storm system. Stay tuned..