191
FXUS63 KMPX 280554
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1254 AM CDT Sun Apr 28 2024

.KEY MESSAGES...

- A cool & rainy day is on tap for Sunday.

- Another round of showers & thunderstorms likely on Tuesday, with a
  few stronger storms possible across S MN.

- Rest of next week looks dry with seasonable temperatures.

&&

.DISCUSSION...
Issued at 248 PM CDT Sat Apr 27 2024

Satellite imagery highlights a potent mid-level trough over the
western CONUS with a more vigorous shortwave evident over the Four
Corners region. Our sfc low is moving over Lake Superior leaving
the Upper Mississippi valley in the wake with northwest or
westerly winds and seasonable temperatures. Speaking of
temperatures, Looking back toward the southern Plains, another
developing sfc low is ejecting out of the Four Corners and will
trek into the Plains later today. Current obs reveal
temperatures in the mid to upper 50s with 10-15mph W/NW winds.
Dry conditions last into the overnight period ahead of the next
system that`ll bring another round of rain & wind on Sunday.

For Sunday, We`ve seen things continue to slow down vs previous
guidance runs. PoPs really ramp up after 12z Sunday morning so
tonight should remain dry for most of us. Our sfc low looks to
remain to our south on Sunday and this will keep us on the
cooler side. High temperatures will be rather brisk, struggling
to hit 50 outside of the I-90 corridor, with a steady rain
expected as well. As for the severe risk, SPC day 2 places I-90
and S MN into the Marginal risk category but guidance doesn`t
seem all to excited with storms in S MN. The better environment
stays off to our south and east in Iowa & Wisconsin as the warm
front really doesn`t clear our counties. An isolated storm or
two will be possible in S MN, particularly late afternoon into
Sunday evening, with a non-zero chance of becoming strong or
severe.

Looking at the week ahead, we`ll dry out and remain cooler to
start the week with high temps in the low to mid 50s on
Monday. The cooldown doesn`t last long as a warm front moves
through Monday night into Tuesday, with temperatures forecast
into the low to mid 70s Tuesday afternoon. Along with the warmer
temperatures comes another, arguably better set up for
thunderstorms Tuesday afternoon. Guidance tracks a healthy
shortwave through the Dakotas on Tuesday. NBM ramps up the PoPs
Tuesday afternoon. This system tracks the cold front through
southern & central MN Tuesday afternoon & evening. This lines up
nicely with diurnal heating maxima and should mean we`re
dealing with convection vs stratiform rain. There will be a
severe risk with a low CAPE/higher shear set up looking to play
out. Forecast soundings highlight a few 100 J/Kg of surface-
based instability and 35+ kts of effective shear & curved
hodographs. Our limiting factor will be the lack of sufficient
lapse rates and that should keep the severe threat to an
isolated strong storm or two vs many. Still, this looks to be an
environment that could support a few marginally severe storms.

Afterward Tuesday, we`ll return to cooler seasonable
temperatures (50s/60s) and a break from precipitation until
next weekend. So why does the forecast have a slight chance for
showers Thursday and Friday if guidance is mostly dry? The NBM`s
make up contains a lot of ensemble members that likely feature
timing differences or features that likely won`t impact us. This
time of year going forward 30 to 40 PoPs are pretty standard
despite no driving system in the deterministic models. So, the
NBM is actually favoring drier conditions which DOES line up
with the bulk of the ensemble guidance. In reality, seasonable
temperatures and a stretch of dry weather will wrap up the week
before next weekend. Guidance is beginning to hint at another
low pressure tracking into the Upper Midwest that would give us
yet another damp/cool weekend.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1237 AM CDT Sun Apr 28 2024

Mixed bag of low VFR/high MVFR ceilings over the terminals
early this morning. General trend was to keep cig heights
around 3k feet over the next few hours. MVFR ceilings will win
out from daybreak onward, with further lowering expected as an
incoming storm system moves in from the south. Initial band of
rain will likely battle some low-level dry air, so opted to
bring -SHRA in at each terminal mid to late morning. More
widespread, sustained rainfall will arrive heading into the
afternoon and will be accompanied by IFR ceilings and
visibility. Chances for thunder look very low, so have continued
the trend of excluding any mention from the TAF set. Winds
increase out of the ENE through the afternoon, with gusts up to
30 knots.

KMSP...Dry weather expected at the terminal until mid-morning at
the earliest. Few hours of -SHRA will precede higher rainfall
rates and expected IFR conditions during the afternoon &
evening. Gusty northeast winds will create crosswind scenario on
the parallels later today.

/OUTLOOK FOR KMSP/
MON...MVFR/-SHRA early, then VFR. Wind E bcmg WSW 15-20G35 kts.
TUE...VFR in the morning, MVFR/-TSRA likely in the
afternoon/evening. Wind SW 10-15G30 kts.
WED...VFR, chc MVFR/-SHRA. W 10-15 kts.

&&

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

&&

$$

DISCUSSION...BPH
AVIATION...Strus