Sunrise 5:27 AM   Sunset 8:55 PM Moonrise 2:03 AM   Moonset 3:40 PM

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FXUS63 KMPX 030029 AFDMPX

Area Forecast Discussion National Weather Service Twin Cities/Chanhassen MN 729 PM CDT Sun Jun 2 2024

KEY MESSAGES

- Thunderstorms, a few with severe weather and localized heavy rain possible this evening, especially across western and central Minnesota.

- Another chance for widespread rain and potentially severe thunderstorms is likely Tuesday.

- Pleasant, mainly dry weather, and breezy weather expected Wednesday into next weekend.

DISCUSSION
Issued at 316 PM CDT Sun Jun 2 2024

With a broad shortwave moving across the northern Plains, we've seen southerly h85 winds and associated moisture transport increase across MN out ahead of that shortwave. This isentropic lift and moisture transport has resulted in the showers that we saw come out of eastern SoDak early this afternoon. SPC mesoanalysis at 18z showed a pocket of 1000+ j/kg of mlCAPE had developed down by St.
James and as soon as this area of showers got to the north of St.
James, a quick uptick in radar reflectivities was noted near Redwood Falls. With SSE low level flow, this instability won't make much progress east, so the intensity of returns we're seeing back west of New Ulm at 230pm are not expected to maintain their intensity into the Twin Cities as they run away from the instability.

For the rest of tonight, there are a couple of things to watch.
First, we've seen storms expand across NoDak, this has been the region of QLCS generation we've been worried about the past couple of days. The other concern we've been seeing from the last few runs of the HRRR and its the potential for the development of scattered storms this afternoon in eastern SoDak/western MN. Basically, the HRRR is developing convection on the northeast fringe of the strong pool of instability over south central SoDak (expected to build to over 4000 j/kg of mlCAPE). The HRRR has been generating some updraft helicity tracks with this activity, indicating the potential for some supercell structures. This potential for more convection to fire ahead of the NoDak activity has only led to more uncertainty on how those storms will evolve through the night. The main trend we've seen with the potential for any lines of storms tonight is less organization. The biggest impact from the lack of organization is we saw our QPF from WPC take a pretty good hit for tonight. Though severe probabilities from the SPC have not changed through the day, given less organization expected, our severe threat for tonight is trending toward the downward direction.

Monday morning, we'll see showers clear out of western WI, with dry weather expected Monday afternoon and evening. Late Monday night, we may see storm potential pick back up as southerly h85 winds and associated moisture transport start to tick up. Models right now are pretty muted on this potential, though as we've seen today, models don't have the greatest track record with generating enough convection when you get into the patterns of broad isentropic lift in a moist environment with a little bit of instability.

Tuesday will feature a strong, negatively tilted short wave working across the Dakotas during the afternoon, with a cold front sweeping across MN. With temperature expected to warm in into the low to mid 80s ahead of the front and dewpoints near 70, we'll have ample instability for storm development. The CAMs that go out that far (NAMnest and FV3) both show a pretty healthy band of storms developing during the heat of the afternoon ahead of the cold front, which makes sense given the forcing. CSU machine learning severe probabilities showed an uptick in severe probabilities across the upper MS Valley, so an upgrade to a Slight Risk when the current Day 3 outlook becomes the Day 2 outlook tonight would not be a surprise.

Not much has changed with the forecast beyond Tuesday. A broad h5 trough will be in place across Canada, with a dip in the flow down into the Great Lakes. This will put us in northwest flow. This will result in some pleasant weather conditions as dewpoints fall into the 40s for several days, with lows in the 40s/50s and highs in the upper 60s to mid 70s. The only drawback for Wednesday through Saturday is we'll likely see northwest winds gusting over 30 mph each afternoon. We mention it will be mostly dry, but we could see a little light rain during this period if we see a shortwave working through in the northwest flow, but there's been little agreement on when/where any of these hiccups may occur.

AVIATION /00Z TAFS THROUGH 00Z TUESDAY/
Issued at 729 PM CDT Sun Jun 2 2024

Scattered storms ongoing now, mostly across central MN into the southeast. The storms were generally moving to the ene and there does look to be a short break this evening before more storms develop and/or move in. After the second wave of storms later this evening into early Monday, ceilings will likely be MVFR for a number of hours, maybe even IFR for a little while early tomorrow morning. Monday will be much quieter after the MVFR diminishes.

KMSP...One wave of storms just tracked barely south of KMSP early this evening. The next batch looks likely to arrive around midnight or 05Z, though it is possible that timing could be delayed. Confidence on the timing is average at best.

/OUTLOOK FOR KMSP/ TUE...VFR early, then MVFR/SHRA with -TSRA/IFR possible. Wind S bcmg W 10-20 kts.
WED...VFR. Chc SHRA. Wind W 15-20G30 kts.
THU...VFR. Wind NW 15-20G35 kts.

MPX WATCHES/WARNINGS/ADVISORIES
MN...None.
WI...None.

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