008
FXUS63 KGRB 211827
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
1227 PM CST Wed Jan 21 2026

Updated aviation portion for 18Z TAF issuance

.KEY MESSAGES...

- Isolated slippery spots on area roads may impact motorists as on
  and off light snow continue through Thursday afternoon.

- Dangerous cold is expected Thursday night through Sunday
  morning. Wind chills are forecast to reach 30 to 45 degrees
  below zero at times.

- An extreme cold watch has been issued from midnight Thursday
  night through noon Saturday.

&&

.DISCUSSION...
Issued at 353 AM CST Wed Jan 21 2026

On and off light snow through Thursday afternoon...

Light snow on the purifier of a surface low currently over NW IL
will continue through daybreak before tapering off. While snow
accumulations will be minor (less than 1") a few slippery spots are
possible on untreated roads. With the exception of a few flurries
across northern WI the region should turn dry for much of the
daylight hours today. Another round of light snow is then progged to
move through the region late this afternoon as another short-wave,
currently over southern Saskatchewan, swings across the region.
Strongest accent with this system is expected across central WI
where 0.5-1" of powdery snow is expected. The rest of the region is
expected to see a dusting to a few tenths. Again while accumulations
will be minor the timing of this system may cause some minor travel
impacts for this evening`s commute. Minor blowing and drifting snow
will also be possible tonight as winds increase to 10-20 mph with
gusts up to 30 mph.

Round of scattered light snow showers is also possible Thursday
afternoon within an CAA regime as low-level lapse rates steepen.
However, the the arrival of drier mid-level air don`t expect much
more than a dusting.

Extreme cold temperatures and wind chills Thursday night through
Sunday morning...

The entire suite of guidance (deterministic, probabilistic,
statistical, and analogous) all point towards a round of dangerously
cold temperatures Thursday night through Sunday morning. The coldest
wind chills are expected Thursday night into Friday morning as
steady NW winds 10-20 mph and air temps 15 to 25 below zero result
in wind chills of 35 to 45 degrees below. A few locations in north-
central may see wind chills approach 50 below early Friday morning.
Highs on Friday are expected to remain well below zero with much of
the region ranging from 5 to 15 below. The coldest air temperatures
of this period of expected Friday night into Saturday morning with
lows forecast to reach 15 to 30 below across the region. If winds
are a able to decouple for a few hours early Saturday morning there
is a 10% chance lows could reach 35 below across parts of northern
WI. In terms of historical context may not see any record low
temperatures, but this is expected to be the coldest air the region
has seen in several years. Extreme Cold Watch remains in effect from
Thursday night through Saturday morning.

Now is the time to make sure your are prepared for the cold. Make
sure you have a least a half tank of gas in your vehicle as well as
an emergency kit. Bring pets indoors and make sure livestock is not
overly exposed to the cold and has access to plenty of food and
water that is not frozen.

Slow moderation looks to occur late in the weekend into early next
week, but temps to remain below normal into next Tuesday. As
temperatures moderate, low predictability exists for snow chances.

&&

.AVIATION...for 18Z TAF Issuance
Issued at 1226 PM CST Wed Jan 21 2026

A mix of VFR/MVFR/IFR flying conditions were observed early this
afternoon, with similar conditions expected over the next 9-12
hours, with some improvement after 03-06Z.

Scattered, light snow has continued from this morning, with a
second wave coming in this afternoon through early evening. Vsby
drops to 1 1/2 to 3SM will come and go with the snow, especially
across central and northern WI. Meanwhile, a few different cloud
layers are present, and flight conditions are bouncing around a
bit based on whether the lowest layer around 1-2kft is SCT or BKN.
The area should settle around VFR bases late this evening after
the snow moves through.

SW to W winds are expected through the TAF period, with gusts of
15 to 25 kts at times.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Extreme Cold Watch from late Thursday night through Saturday
morning for WIZ005-010>013-018>022-030-031-035>040-045-048>050-
073-074.
&&

$$

DISCUSSION.....GK
AVIATION.......KLJ

NWS GRB Office Area Forecast Discussion