Most of last week’s forecasts played out pretty much as expected, with high pressure dominating our region bringing plenty of sunshine, dry conditions and warm temperatures. A big question mark is whether this will be our new pattern — or was this only a temporary reprieve from what we experienced in April?
Normally I am fairly confident with the start of the forecast period, but that is not the case this week. The weather models show a slow-moving upper low developing and impacting our region starting on Wednesday and lasting until the early weekend. As you know, upper lows are notoriously difficult to forecast, but I’ll do my best to paint the big picture.
The models show this low slowly developing during the first half of the week over the central U.S. before kicking northward into eastern Montana early on Wednesday. We’ll see clouds and showers covering pretty much all of southern and central Manitoba on Wednesday with the best chance of significant rain over far western regions. This low is then forecast to slowly drift to the east on Thursday and Friday. The question is, how far north will the low push before drifting east? A southern track along the border will bring rain to southern regions late Wednesday, while a more northerly track will mean showers for southern regions and steady rain farther north through central regions.
All the models have the low out of our region by Friday, but we can expect a strong cool northerly flow behind the low as a large arctic high slowly builds southward. Expect some fairly cold temperatures to start off the weekend, with readings coming in around the bottom end of the usual temperature range for this time of the year. As the high continues to slowly build in, expect temperatures to moderate early next week under strong spring sunshine. We should see daytime highs back up toward the 20 C mark by Tuesday of next week.
Usual temperature range for this period: Highs, 13 to 25 C; lows, 0 to 9 C.