Hail threat spikes briefly Friday night before cool weekend

Following the hottest and most muggy day of the week, there’s a mini severe weather window, in the White Earth, Leech Lake, and Red Lake Reservation areas. The weekend is considerably cooler, with more widespread chilly rain on Monday.

Storm threats, timing Friday

In the midst of a humid and hotter Friday, storms are beginning to bubble up in the Dakotas, along with north-central Minnesota. They will push east Friday evening into the early overnight and will deliver a brief severe weather threat for parts of Minnesota, especially around Walker, Grand Rapids, Detroit Lakes, Bemidji, and Brainerd areas.

All week long, we’ve had a slight risk of severe weather, Friday evening, encompassing, almost all of Minnesota. We think that the level two, shaded yellow, risk area has been a little bit too large. The storms have also sped up timing by about one hour, compared to where things stood earlier in the week. The severe weather window is roughly 7-10 pm on Friday, though it could begin a little earlier and could remain a little later. the primary threat actually looks to be large hail.

When consulting a sounding, in this case, a weather balloon mockup that we created with software, there were 103 matches for similar storms that produced damaging hail in that part of Minnesota. There were much fewer damaging wind and tornado case studies in the similar part of the state. We could still have an isolated tornado around 7 pm in North Central, Minnesota, and then some brief damaging winds until a little bit closer to midnight, but hail is the biggest deal this time around. By the time this Updraft is published, the storms have already started.

Given that our drought did not see much improvement this week, we could also use the rain in almost all parts of the state. Rain will mostly be confined to the northern half of Minnesota and should be heaviest in the north eastern part of the state once these storms become more of a squall line later on.

Weekend planner

This all wraps up very early in the day on Saturday. There might be some fog on your Saturday where it rained heavier. We have often on cloud cover and much cooler feel. High temperatures are probably going to run about 10 to 15° below where they were on Friday. With a mid-level low trailing the cold front, that will often produce often on darker clouds. While one or two sprinkles are possible, widespread rain appears fairly unlikely for Minnesota on Saturday.

Sunday is still the toughest call on precipitation for the next week or so. We do think that there will be some persisted and cooler rain showers for the southern 1/3 of Minnesota on Sunday. That’s actually exactly the kind of stuff that we need for a drought helper. High temperatures are likely to be even cooler, in the middle 60s for much of the state.

Monday is setting up to be our coldest high temperature since the middle of May. We are going to have widespread rain through much of the North Star State. Those that do not get rain this time probably did get the rain on Friday; this balancing out should help everybody at least a little bit with the drought.

Many will not make it to 70° heading into Monday afternoon. That even includes the usual hotspots in the Mississippi and Minnesota River Valleys, plus the urban heat Island around the Twin Cities. One update is that Monday is not quite as cold as it once appeared, but we’ll still be well below average.

Following this quick taste of fall – and yes, that does include leaves dropping early in the rain and winds - we slowly begin to climb back above average heading closer to next weekend.