383
FXUS63 KARX 220908
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
308 AM CST Sat Nov 22 2025

.KEY MESSAGES...

- Dry through Sunday night with above-normal temperatures.

- Rain chances from Monday morning through Tuesday...and then a
  gradual transition to rain and snow on Tuesday night...and
  snow Wednesday.

- Much colder Thanksgiving and beyond with wind chills as low as
  the single digits

&&

.DISCUSSION...
Issued at 304 AM CST Sat Nov 22 2025

Today - Sunday: Dry with Warming Temperatures

A quiet and pleasant weekend will be on tap for the Upper
Mississippi Valley. Northwest flow aloft will prevail with a
weak shortwave trough passing to our north and east today. At
the surface, a weak low to our north will drag a "cold" front
through the region later this afternoon. As this system is
coming from a Pacific based airmass and not Arctic, temperatures
should generally remain moderated through the weekend. Highs
today and tomorrow will be above normal in the upper 40s to mid
50s with lows in the mid 20s to low 30s thanks to a slight bump
in low level moisture.

Monday - Wednesday: Precip Chances Return and Cooling Off

A cutoff upper low across Southern California and Western
Arizona is expected to eject northeast through the Colorado
Rockies and into the Plains Sunday into Monday. At the surface,
a low pressure system will follow a similar path out of the
Desert Southwest. As this system moves out of the Rockies and
into the Plains, it will begin to drag some Gulf moisture from
Texas northwards into the Upper Midwest. This increase in
moisture will allow for a broad swath of rain to take shape over
much of the Central CONUS, impacting our area after 12Z Monday.
Overall rain chances look to peak late in the day on Monday
with chances for PoPs in the 80-95% range across the entire
area. While chances for rain continue to increase, overall
totals generally remain on track with most locations averaging
between 0.20-0.50 inches through Wednesday morning. LREF grand
ensemble (GEFS, ENS, GEPS) probabilities of greater than 0.25
inches of rain through Tuesday night range from 25-60% with
probabilities dropping to less than 15% for totals at or above
0.50 inches.

While the aforementioned cutoff upper low is moving into our
area Monday from the southwest - rejoining the main upper flow,
yet another trough appears to start taking shape across Western
Canada. This is expected to drop east/southeast behind the first
upper low with their respective surface lows joining forces
Monday night into Tuesday. While this is all a bit complicated,
the end result is a fairly stout upper trough and surface low
over the Upper Midwest during the day on Tuesday. This Canadian
low is expected to bring a potent Arctic airmass behind it so
temperatures will start to drop as winds shift to the
west/northwest. While the best moisture will get scoured out
with the first wave on Monday, lingering precip chances remain
through Wednesday morning, mainly for areas along and north of
I-90. Precip should largely stay as rain through the day on
Tuesday before the cold airmass really starts to work its way in
and transitions the precipitation to a rain/snow mix overnight.
Precipitation should finally mix all the way to snow by
Wednesday morning. Any snow is expected to be light/fluffy in
nature and accumulations should be minimal. As the low departs
on Wednesday and the pressure gradient tightens on the backside,
west/northwest winds are expected to pick up to between 10-25
mph with higher gusts, especially in the afternoon. While
temperatures Monday and Tuesday will hold steady in the upper
40s to low 50s, highs Wednesday will take a plunge into the low
to mid 30s.

Thanksgiving - Next Weekend: Bitter Cold Makes its First
Appearance

As a strong arctic high pressure works its way into the
Northern Plains behind the departing system, temperatures will
continue to take a hit, especially morning lows which are
expected to fall into the teens both Thursday and Friday
mornings. Daytime highs will struggle to climb above freezing
into the weekend with continued northwesterly winds advecting
cold, dry air into the region. Wind chills, especially during
the morning hours, could very possibly be in the single digits
which would be a first for this late fall season. These cold
temperatures look to stick around generally through the end of
the month with long range ensembles showing a prolonged cool
down through the start of December.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1122 PM CST Fri Nov 21 2025

Clear skies have allowed surface cooling near surface dewpoint
temperatures, raising concerns of visibility reductions
primarily along river valleys through the early morning hours.
Local La Crosse, WI webcam imagery suggests formation of a fog
dome over KLSE at 21.06Z TAF issuance while satellite imagery
and surface observations aren`t registering similarly yet.
Further forecast difficulty from a changing low level pattern
through the overnight hours. Model solutions appear quicker than
low level observations for center of low level high pressure as
radar wind profiles show anticlockwise low level flow still
upstream of the local forecast area. Therefore, have opted
pessimistically with FG at KLSE, including TEMPO MIFG at KLSE
through the early morning hours. Additionally, VFR visibility
<10SM seen west of the Mississippi River Valley will linger
until low level wind field increases in wake of passing high
pressure. Should FG be more substantial and build off the
surface, will require AMD at KLSE over the next couple of hours.

Winds rotate clockwise through the 21.06Z TAF period. Fog
impacts Sunday morning will be limited by increased off surface
winds.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.

&&

$$

DISCUSSION...Barendse
AVIATION...JAR