244
FXUS63 KARX 111137
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
537 AM CST Thu Dec 11 2025

.KEY MESSAGES...

- Winter system today shifting a bit farther southwest and bulk of
snow likely away from the local area. Parts of NE IA could still
receive an inch or two.

- Bitter to dangerous cold moves in for the weekend. High temps in
the single digits above/below zero. Coldest Sunday morning. Wind
chills from -20 to -35F Sat night through Sun morning. Cold Weather
Advisories are expected. Plan now for this cold weekend.

- More seasonable temps return for next week with a few non-snowing
days too.

&&

.DISCUSSION...
Issued at 140 AM CST Thu Dec 11 2025

> TODAY-FRIDAY: a couple more shortwaves provide snow chances - but
mostly south/north of the local area.

The first shortwave will streak from the PAC NW, spinning across the
northern plains and then IA later this afternoon/evening. Upglide on
the 280:295K surfaces precede it with good, sloping Fgen from
southwest to northeast. QG is disjointed, not vertically stacked nor
overly strong. There is a little low level feed of moisture on the
southern flank of the system with ample saturation per forecast
soundings, RH fields.

Enough pop and saturation to produce another band of snow across
parts of the region - with a few inches likely. Where the band lays
out is the main question. Ala recent, similar events, the global
models (GFS/EPS) haven`t moved much off their original depictions
days ago - stretching the snow band from southwest MN, across
central IA into central IL. Real good support from their ensemble
suites, respectively. Also ala recent events, the CAMS models
(namely the RAP and HRRR) shifted north over the past day...but now
are trending back southward - more inline with the GFS and EC. Think
this is the way to go and will align the snow chances with the
global outlay.

With that trend, the primary snow band sits just southwest of the
local area. 1/2 to 1" currently progged for portions of SE MN,
southwest WI. 1/2 to 2" for NE IA...although the probabilities for
2" currently sit at 20%. No need for a winter weather advisory at
this time.

Will monitor real-time obs along with meso guidance to see if a
shift back north might manifest.

The second shortwave is progged to drop across portions of northern
MN/northern WI Fri/Fri evening. Has some QG convergence through the
layers but weak low level warming and no Fgen to speak of. Also, RH
isn`t impressive and only meager QPF. All in all, a weaker shortwave
but has enough going for it to produce an area of light snow, albeit
with minimal amounts. High chances, low amounts favored in this
scenario. Current track keeps the higher local chances north of I-
94.


> WEEKEND: very cold! Highs might not warm above zero for some.

A hefty slug of cold air follows in the wake of the second, more
northern tracking shortwave Friday. 850 mb temps progged to fall
from around -8 C at 12z Friday to -20 C by 18z Sat. NAEFS and EC 850
temp anomalies near -2...and expect these to increase over the next
couple days. EFI are on aboard with a strongly anomalous cold
outbreak for the weekend. Max and Min Ts range from 0.8 to 0.95 with
a non zero SoT. At KLSE, over 75% of the EPS and GEFS members
suggest it won`t warm above zero through the weekend. The LREF
paints 80-100% chances for -10 F or colder Sunday morning area wide.
Brrr indeed.

Winds, while not expected to be "strong", could blow from 10 to 25
mph at times Friday through Saturday. This will add a signficiant
bite to the already cold conditions.

Cold Weather Advisories are likely Sat night through Sun morning.

A streaking ripple in the upper level flow looks to take a similar
path as the shortwave this afternoon/tonight - moving southeast out
of the northern plains and across IA on Sat. If this track holds,
most (if not all) of any impactful snow will stay well south of the
local area. Model blend might be a bit too far north with related
snow chances but QPF/snow totals hold more southward. Will stick
with the blend for the details for now.


> NEXT WEEK: pattern shift! Temps more inline with the season
return. Not quite as "busy" for snow chances - more dry days.

GEFS/EPS shift east an upper level ridge along the west coast as we
move into the new week. Excellent agreement in the all the WPC
clusters. The ridge doesn`t stay around long, but the upper level
flow stays fairly zonal and progressive.

The big upshot from all this is a return to more seasonable temps -
potentially a few degrees above. Temps could fluctuate a bit more
moving into the following weekend, but no signficiant cold (after
this weekend) looming on the horizon.

As for pcpn chances, looks like we could get a break from the every
other day snow makers that have been plaguing the region over the
past week or so. Some consensus via a bulk of the ensemble members
for a system to traipse across the northern plains/upper mississippi
river valley around Thu. Current solutions suggest a stronger system
that could pack a punch - for some. A lot to navigate between now
and then, with likely shifts in track/timing. A system to keep an
eye on.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 537 AM CST Thu Dec 11 2025

MVFR CIGS gradually diminish through the morning for portions of
SE MN, NE IA, and SW WI, otherwise VFR conditions elsewhere.
CIGS hang just above MVFR flight category, between 3 and 6kft,
for most of SW WI and portions of SE MN through the rest of the
TAF period. MVFR to IFR CIGS and visibilities enter portions of
SE MN and NE IA at the same as light snow enters these areas.
Snow should end by midnight improving visibilities but CIGS
remain in the MVFR to IFR range for SE MN, NE IA, and far SW WI
for the remainder of the TAF period. Light and variable winds
for the day as winds start out northwesterly then circle around
southward for the rest of the morning and afternoon, then
shifting northerly for the evening and overnight.

&&

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

&&

$$

DISCUSSION...Rieck
AVIATION...Cecava