391
FXUS63 KARX 111936
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
136 PM CST Tue Nov 11 2025

.KEY MESSAGES...

- Warmer for the remainder of the week with the warmest days
  being Friday and Saturday as highs reach the upper 50s to low
  60s.

- Breezy through Wednesday afternoon with northwesterly winds
  gusting to 25 to 35 mph.

- Mainly dry for the next seven days with token (10-30%) chances
  for rain late Saturday through Monday.

&&

.DISCUSSION...
Issued at 135 PM CST Tue Nov 11 2025

Breezy Through Wednesday Afternoon:

An occluding surface boundary is sliding through the region
this afternoon, with a downslope-modified airmass trailing in
its wake. Thus, temperatures have been warming behind the
frontal passage in southern Minnesota with readings topping out
in the 40s today, possibly near 50 towards the I-35 corridor. A
modest pressure gradient between the low in southwestern
Ontario and a strengthening ridge over the High Plains, coupled
with modest daytime mixing, will allow for gusty northwesterly
winds this afternoon and again on Wednesday. Winds at the top of
the mixed-layer top out around 25-35 kts (30-40 mph), and these
can be considered the reasonable strongest wind gusts we`ll see
today and Wednesday afternoon (20% chance at any given spot,
highest at higher elevations). The pressure gradient relaxes
from west to east Wednesday evening as the ridge expands
eastward, dropping the winds with it.

Sky Conditions for Aurora Watching Tonight & Wednesday Night:

A vibrant aurora display may be visible across the region
tonight and especially Wednesday night, when a G4 geomagnetic
storm watch is in effect. Relatively dry mid to lower
tropospheric profiles should limit dense cloud coverage, but
cyclonic flow over the next 24-36 hours will keep the potential
for bouts of clouds to infiltrate the region. Thin stratus
clouds rotating around the aforementioned Ontario low pass
through the region between now and midnight, mainly impacting
areas in Wisconsin. Skies clear out after midnight, but recent
CAM runs show high cirrus spreading in after midnight on the
nose of a 140-kt jet streak.

For Wednesday night, despite the building surface ridge,
20-30kft high clouds may muddle the skies. Nevertheless, high
ice clouds can be rather fickle and contain breaks, so keep an
eye on the forecast as we go through the day tomorrow.

Warming up Through the Week:

The main weather story for the upcoming week will be continued
warming temperatures ahead of a strong upper tropospheric ridge
amplifying over the Rockies/High Plains, culminating with the
warmest readings on Friday or Saturday.

The main uncertainty in the forecast revolves around the
phasing of the northern and southern stream upper tropospheric
waves, with recent (last 24-36 hour) runs of the medium range
solutions now favoring the streams remaining discrete. This
results in a faster progression of the northern stream wave on
Saturday, bringing the cold front through during the morning on
Saturday and limiting the degree of daytime heating before cold
air advection ensues. It will still be a nice start to Saturday
(highs in the 50s to low 60s, warmest in southwest WI), but just
not quite as warm as previously advertised and temperatures
would fall through the afternoon.

Indeed, the deterministic GFS/EC runs now keep the warmest air
to the south for both Friday and Saturday and their respective
aggregate ensemble suites are reflecting this trend (moreso the
EPS than the GEFS, though the GEFS may be suffering from an
over-mixing bias). Temperatures return to seasonal norms for
next week under a more northwesterly flow pattern.

Low End Rain Chances Return for Sat - Mon:

The probability for precipitation with the cold frontal passage
on Saturday continues to fall as the wave opens up and the
synoptic forcing wanes. For now, kept the NBM 10-20 percent PoPs,
but if trends continue these PoPs may be removed. This leaves
late Sunday into Monday as the only notable window for
precipitation in the seven day forecast, tied to a poorly-
resolved vort lobe ejecting under the base of a synoptic ridge.
The NBM/LREF precipitation probabilities are rightly only in the
20-30% range for Monday and expect that these will need further
refinement over the course of the week. Can`t fully rule out
some of this precipitation falling as snow, but again, the
forecast remains too fluid to nail down specifics.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1130 AM CST Tue Nov 11 2025

A band of low VFR/high MVFR ceilings over northern MN/
northwestern WI drops southeastward this afternoon and evening.
While MVFR ceilings are anticipated north of an EAU to ISW
line, there is a 10-20% chance that these ceilings could sneak
as far south as LSE this evening. VFR conditions are expected
for the remainder of the TAF period and into Thursday. Winds
veer to the northwest this afternoon, gusting to 20-25 kts.
Winds remain around 10-15 kts with similar gusts increasing
during the day on Wednesday.

&&

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

&&

$$

DISCUSSION...Skow
AVIATION...Skow