179
FXUS63 KMPX 232035
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
335 PM CDT Thu May 23 2024

.KEY MESSAGES...

- Showers & thunderstorms expected overnight into tomorrow
  morning. A Marginal Risk of severe weather (mainly damaging
  wind) across southern Minnesota.

- Cooler Memorial Day weekend with periodic chances for rain,
  mainly on Sunday.

&&

.DISCUSSION...
Issued at 211 PM CDT Thu May 23 2024

Thunderstorms will become more widespread across the eastern
Dakotas this evening ahead of an advancing cold front & surface
low. The bulk of this activity is expected to remain along &
north of a stationary boundary stretched across north-central
Minnesota. A few isolated showers & thunderstorms can`t be ruled
out across our area of central Minnesota, but strong/severe
weather is not anticipated with dew points in the mid-40s. Quiet
weather is expected this evening, but becomes more active
overnight as a line of showers & thunderstorms along the cold
front advances through Minnesota & Wisconsin after midnight &
continues through tomorrow morning. Farther south along the
front where surface-based instability is higher, a mesoscale
convective complex is expected to develop tonight across eastern
NE/SD, and continue eastwards through Iowa overnight. Most CAMs
have the northern edge of this complex extending into at least
far-southern Minnesota, so a threat for damaging winds will
exist across these areas during the early morning hours.
Surface-based instability sharply decreases farther north
towards the Twin Cities metro & central Minnesota so less of
threat for severe weather is expected tomorrow morning, but
still can;t totally be ruled out. Rainfall amounts through
tomorrow morning are generally expected to be between 0.25-05."
across central MN & western Wisconsin, with amounts closer to
0.75-1" possible across southern Minnesota where thunderstorms
are more likely.

The morning showers & thunderstorms will be east of the area by
mid-morning, and then the question becomes how far east will the surface
front/boundaries by by the afternoon & whether any additional
showers or thunderstorms can redevelop behind the morning
convection. For now, chances for scattered afternoon showers &
thunderstorms look highest across western Wisconsin, with
perhaps more isolated convection farther east into the I-35
corridor & central Minnesota. Rainfall amounts with the
afternoon precip will range from 0.5-1" across central Wisconsin
where the coverage will be greatest, to maybe up to 0.1" from
any isolated showers across eastern & central MN.

Somewhat unsettled weather continues over the Memorial Day
weekend as a deep trough over the western half of Canada ejects
a number of shortwaves over the Upper Midwest. Periodic chances
for showers & a few thunderstorms will accompany each of these
waves, so we`ll carry a general 30-50% chance of rain through
the weekend (although there will be more dry periods than wet
periods). The best chance for a widespread & soaking rain comes
Sunday with a more organized shortwave moving through the
central plains & mid-Mississippi valley. This system will
largely pass south of our area, but rainfall amounts of 0.5-1"
could extend north into southern & central MN & western WI.
Outside of Sunday, isolated to scattered showers are possible at
times this weekend with coverage expected to be somewhat
diurnally driven during the afternoon. Temperatures will be on
the cooler end this weekend from the lower heights aloft & cloud
cover/precipitation, with daytime highs generally in the 60s to
low 70s.

Looking ahead, ridging aloft builds into the central CONUS into
the middle of next week, leading to warmer temperatures & at
least a few days of dry weather.


&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 102 PM CDT Thu May 23 2024

VFR conditions into this evening with FEW/SCT cumulus through
sunset. Thunderstorms are expected to develop across eastern ND
& northwest MN by late this afternoon, with a low (10-20%) of a
thunderstorms developing far enough south to impact AXN by early
evening. Otherwise, a line of showers & thunderstorms will move
into Minnesota after midnight, reaching eastern Minnesota by
sunrise & western Wisconsin by 7-8 AM. Thunder chances are
highest across southern Minnesota (MKT) but will include a
PROB30 at RWF/MSP/RNH/EAU for 2-3 hours tomorrow morning.
Visibility is mainly expected to be borderline MVFR/IFR during
the showers tomorrow morning, with periods of IFR possible
during thunderstorms. Ceilings will also lower as the rain
begins & linger into at least mid-morning, with most terminals
expected to see a few hours of MVFR tomorrow morning. Winds will
generally be southerly to southeasterly this afternoon with
speeds around 10 kts. Winds become predominately southeasterly
this evening & overnight with gusts of 20-25 kts developing as
the rain begins. A wind shift to southwesterly is expected after
the rain ends, with gusts around 20 kts remaining through the
morning.

KMSP...Showers and thunderstorms could begin as early as 5 AM,
but 6-7 AM is the more likely start time as of now. A few
rumbles of thunder are likely, but will wait for confidence on
the thunder chances to increase before going prevailing TSRA in
the TAF.

/OUTLOOK FOR KMSP/
SAT...VFR. Wind SW 10 kts.
SUN...VFR. Chance -SHRA/MVFR. Wind E 10-20 kts.
MON...VFR. Chance -SHRA/MVFR. Wind NW 10-20 kts.

&&

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

&&

$$

DISCUSSION...ETA
AVIATION...ETA