076
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.

&&

$$

DISCUSSION...MPG
AVIATION...TDK