384
FXUS63 KMPX 221124
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
524 AM CST Fri Nov 22 2024

.KEY MESSAGES...

- Cooler weather persists into next week, with temperatures falling
 even further by Thanksgiving Day.

- A small chance for a few showers north of I-94 Sunday into
  Monday.

&&

.DISCUSSION...
Issued at 304 AM CST Fri Nov 22 2024

The main story this morning are the stark differences between those
areas stuck under stubborn stratus clouds versus those with clear
skies, with western Minnesota seeing lows dropping into the upper
teens compared to low to mid 30s in eastern MN to western WI where
the clouds persist. We have yet to see significant fog development
this morning, however by this time tomorrow morning this may be a
different story with weaker winds as the system moves away and
radiational cooling helping to drop temperatures to dew points with
a bit of moisture left over from the now melted snow and the low
level cloud cover having pushed to the east. We will continue to see
colder temperatures through the weekend and into next week with the
coldest weather of the year so far expected by Thanksgiving Day and
into the following weekend, with a lack of active weather across the
region. Our upper level flow remains zonal to northwesterly as the
deep surface low moves towards the east coast by tonight with a lack
of a dominant weather system over the region to influence the
weather as surface conditions remain stagnant. Late Sunday into
Monday would bring our next best chance for precipitation primarily
north of I-94 as the southern stream jet remains too far south to
produce synoptic scale lift over the area, meaning we rely on a weak
surface cold front from a Canadian system to bring weak showers
primarily north of I-94, with most of the area remaining dry.

After the slim chance of precipitation departs the area by Monday
evening, we continue to trend cooler as ridging sets up over Alaska,
causing a surge of colder air aloft to slide southeast towards the
northern plains. The southern stream jet remains too far south to
push the cold air out faster, and with weak surface high pressure
and general subsidence we can expect to see some of that colder air
begin to mix down to the surface later in the week. A few of the
ensemble members would try to force a bit of weak precipitation by
late Wednesday night, however this appears to be a lackluster chance
at best driven mainly by an overactive potential vorticity anomaly
present on the northern fringe of the southern stream jet. Guidance
is generally sporadic in bringing in further small precipitation
chances, with the only real consensus being persistent northwesterly
flow aloft bringing arctic air closer and closer to the region later
in the week. By Friday, we could be looking at highs struggling to
get out of the mid 20s, marking a cold end to the month as it likely
persists into early December.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 520 AM CST Fri Nov 22 2024

No reason to buck the trend with continued low MVFR/IFR CIGS for
most of the period with a brief gap from roughly 20-02z where we
could scatter out enough to put as at SCT instead of BKN.
Low level moisture and cloud cover will stick around through the
end of the period before finally beginning to lift and scatter
out fully on Saturday.

KMSP...Besides the brief window where we could scatter out, we
remain low MVFR throughout the period. Forecast soundings don`t
move the deck of stratus out through at least 18z Saturday.

/OUTLOOK FOR KMSP/
SUN...VFR. Wind SE 5-10kts.
MON...VFR/MVFR, chc -SHSN. Wind NW 10-15G20kts.
TUE...VFR. Wind NW to SE 5kts.

&&

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

&&

$$

DISCUSSION...TDH
AVIATION...TDH