NWS-Green Bay Forecast Discussion

						FXUS63 KGRB 011151
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
551 AM CST Sun Feb 1 2026

Updated aviation portion for 12Z TAF issuance

.KEY MESSAGES...

- Light snow is forecast to move across the region this afternoon
  and tonight. Accumulations of a half inch (60-80% chance) to one
  inch (10-30% chance) are expected. Slippery travel conditions
  will likely develop, and may extend into the Monday morning
  commute.

- A potent clipper system may impact the area next Thursday and
  Friday. While significant timing and track uncertainties
  remain, this system has the potential to bring accumulating snow
  and gusty winds.

- Highs in the 20s will be common for much of next week, possibly
  exceeding 30 degrees at a few locations Thursday and Friday.

&&

.DISCUSSION...
Issued at 252 AM CST Sun Feb 1 2026

Mostly clear skies and light S-SW winds were observed across the
region early this morning as surface high pressure gradually
shifted east. Temperatures were generally in the single digits
above and below zero. A clipper low pressure system was moving
through southern Manitoba, with a cold front extending south
along the Dakotas/MN border. Widespread light snow with this
system was overspreading MN.

CAMs show the leading edge of light snow reaching NC/C WI later
this morning, but eroding as it encounters drier air. This occurs
for several hours until forcing with the cold front and short-
wave trough push a band of steady light snow (VSBYs mostly 1 1/2
to 4 miles) through the forecast area later this afternoon and
tonight. Have maintained high pops (around 80 percent) within the
main snow band, but did slow the arrival time down by an hour or
two. Most locations should receive a half inch to an inch of snow,
and roads will likely become slippery in spots. The snow should
end by Monday morning; with the exception of scattered lake-
effect snow showers in far NC WI, though slippery stretches could
linger into the morning commute.

A brief period of high pressure will bring dry conditions late
Monday through Wednesday as the upper-level pattern re-amplifies.
An upper ridge will then strengthen over the western U.S. while a
mean trough reinforces itself over the East. This set-up will
pave the way for a potentially more significant clipper system
Thursday into Friday. Model guidance indicates an intensifying
low pressure system crossing the Great Lakes, though differences
in timing and track persist at this point. Given the potential for
strong dynamics, this system will need to be monitored for both
accumulating snow and strong wind impacts. Current probabilities
for snowfall greater than 1 inch are highest (50-70%) across the
northeast third of the CWA, with a 30-50% chance of 2+ inches
over Vilas County and far northeast WI, including Door County. If
this system tracks far enough north, there may be enough warm air
pulled into the region to support a rain/snow mix in the south.
There is potential (30-50% chance) of gale force gusts near
Deaths Door as the system departs Friday and Friday evening.

Temperatures remain on the milder side through most of the period,
with highs mainly in the 20s, and even some low to mid 30s in
C/EC WI Thursday into Friday. A brief shot of colder air arrives
in the wake of the late week clipper system, as 850 mb
temperatures drop to -20 to -25 C. Below normal temperatures are
likely on Saturday, but should rebound a bit by the end of the
weekend.

&&

.AVIATION...for 12Z TAF Issuance
Issued at 539 AM CST Sun Feb 1 2026

Clouds increase and ceilings lower through the morning as the
next system approaches from the west. Patchy light snow is
expected to commence around 19z/Sun at AUW/KCWA/KRHI, with
steadier snow developing a few hours later. The steadier snow
should reach ATW/GRB/MTW during the early to mid evening. Snow
tapers off at the western TAF sites around 06z/Mon, and
08z-09z/Mon at the eastern sites. MVFR and intermittent IFR
conditions are expected within the main snow band. Total snow
accumulations of 0.5 to 1.0 inch are expected for most sites by
late tonight.

A period of LLWS is expected to impact the RHI TAF site this
morning through early afternoon. Otherwise, surface winds will
become SSW and gust to 15 to 20 kts during the day, before
veering west with the passage of the cold front tonight.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION.....Kieckbusch
AVIATION.......Kieckbusch