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FXUS63 KMPX 281933
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
233 PM CDT Tue May 28 2024

.KEY MESSAGES...

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- Scattered showers this afternoon diminish this evening and
overnight. Skies remain clear throughout Wednesday.

- Shower and storm chances increase late Thursday into Friday,
persisting through the weekend. Overall coverage will be isolated to
scattered, no strong storms expected.

- Our next chance for more widespread showers and storms arrives by
Monday next week.
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&&

.DISCUSSION...
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Issued at 232 PM CDT Tue May 28 2024

Scattered showers and a few thunderstorms continue to drift
southeast this afternoon, as cold air advection from northwesterly
flow aloft produces a bit of lift before the system pushes eastwards
overnight. Shower and storm activity should begin to diminish by the
evening, with skies gradually clearing overnight ahead of mostly
clear skies tomorrow. There has been a bit of lightning observed
within a few of the storms this afternoon as well as some pea sized
hail, however nothing more than this is currently expected due to
the relatively weak forcing and diminishing moisture profile. As
skies clear out and with additional sunshine, temperatures tomorrow
should end up more than 5 degrees greater than this afternoon as
highs reach the low 70s Wednesday and mid to upper 70s on Thursday,
as winds shift southerly over the next few days.

As we head towards Thursday evening and into Friday, chances for
showers and storms will rise as a broad 850mb jet begins to stream
gulf moisture towards the region, with this jet strengthening over
the Dakotas on Thursday before moving eastwards with a broad 500mb
trough into Friday. The influx of moisture and broader forcing from
the trough should allow for a brief period of higher coverage of
showers and storms on Friday before we settle back into more
isolated coverage over the weekend. There is only a small chance for
thunderstorms as the timing works out such that the heaviest rain
moves through Friday morning with limited instability to work with,
generally under 250 j/kg SBCAPE and 500 j/kg MUCAPE. Low level shear
is enough to maintain a storm should it get going, however the vast
majority of rainfall will come from more run of the mill showers.
Zonal flow aloft will continue to produce small impulses and
shortwaves over the weekend with slight chances for showers and
storms throughout, although we still see a general lack of
instability to produce anything resembling a severe thunderstorm.

The best chance for more sustained and widespread rainfall looks to
arrive early next week by Monday morning with solid consistency
between deterministic synoptic scale guidance on a plume of moisture
flowing northwards from the Gulf, allowing for increased coverage of
showers and storms via an arriving trough. Given the increased
moisture, this would also be our best opportunity for a few stronger
storms, however we are far enough out such that models have yet to
catch up on any major instability being present amidst the rainfall.
QPF response is relatively muted due to the convective potential,
however unlike the weekend showers should result in at least some
rainfall for the majority of the coverage area. The pattern beyond
Monday shows potential for an occlusion over the Great Lakes to
produce more cold air advection wrap around showers, however until
we get closer this is low confidence for now. Overall, a fairly
classic summer pattern is ahead of us with sporadic chances for
showers and weak storms with a lack of significant instability for
any stronger storms within the current forecast.
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&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1215 PM CDT Tue May 28 2024

Radar and satellite imagery shows bubbling cumulus over the
region within northwesterly winds aloft, producing isolated to
scattered showers which will continue into the afternoon.
Showers will remain rather weak overall with visibility
generally remaining above 6 miles, with CIGS dropping within
showers to around 3500ft. VFR conditions are expected to
continue with only a small chance for a stronger shower
producing MVFR CIGS/Visibility for the first few hours of the
period. After 23-00z, skies will begin to scatter as showers
exit the area with clearing continuing overnight. Winds will be
320-350 at or just above 10kts through 00z, shifting towards
030-060 at or below 5kts by 09z.

KMSP...Depending on how quickly shower activity moves eastwards,
we may need an additional TEMPO group with the 21z amendment to
cover showers lingering for an additional couple hours.

/OUTLOOK FOR KMSP/
THU...VFR, chc MVFR/-SHRA late. Winds S 10-15G25kts.
FRI...VFR/MVFR, chc IFR/-TSRA. Winds S 10kts.
SAT...VFR/MVFR, chc -TSRA. Winds SW 10kts.

&&

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

&&

$$

DISCUSSION...TDH
AVIATION...TDH