Forecast Discussion for GRB NWS Office
415
FXUS63 KGRB 082149
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
349 PM CST Mon Dec 8 2025

Forecast discussion for routine afternoon forecast issuance

.KEY MESSAGES...

- A clipper system is expected to bring a swath of 1 to 3 inches
  of snow across the area tonight. Highest amounts across far
  northern Wisconsin.

- A more potent clipper system is expected to bring another round
  of snow to the area late Tuesday afternoon into Wednesday
  morning. This system is expected to produce 3-5 inches of snow
  over much of the forecast area, with a narrow band of higher
  amounts closer to 6 to 7 inches. A Winter Storm Watch is in
  effect for this system.

- Much colder temperatures arrive for the end of the week. Wind
  chills of -10 to -30 are possible Friday night into early
  Saturday and again Saturday night into Sunday morning.

&&

.DISCUSSION...
Issued at 349 PM CST Mon Dec 8 2025

Short Term...Tonight and Tuesday

Ahead of an approaching clipper system, low-level moisture moved
into the area bringing low-level clouds and flurries to central
and north-central WI this afternoon. Southerly winds have also
allowed for low-level moisture/clouds to move inland from Lake MI
resulting in scattered flurries across eastern WI this afternoon.
These conditions are expected to continue until the aforementioned
clipper system moves into the area this evening and overnight.

While not very strong, this clipper system will spread snow
across the region from west to east from late this evening and
taper off/end by early Tuesday morning. By Tuesday morning,
snowfall amounts of 1 to 3 inches are expected across the entire
forecast area. The higher snowfall amounts are anticipated across
far northern WI where the better forcing will be located. While
there may be minor travel impacts to the Tuesday morning commute
on untreated/secondary roads, there is also potential for a brief
period of freezing drizzle Tuesday morning, as forecast soundings
indicate the loss of ice crystals aloft as the snow is ending.
Therefore, a few spots may become slick Tuesday morning following
the departure of the snow. Additionally, gusty southerly winds
will accompany the clipper system with gusts to 20 to 25 mph,
which will cause reduced visibility at times while the snow is
falling.

There will be a lull in precipitation and winds late Tuesday
morning through the late afternoon before the next clipper
system arrives. During this time, a few breaks in the clouds are
possible as high temperatures climb into the mid 20s to low 30s.
The next clipper system will arrive from the west late Tuesday
afternoon into the evening, bringing the chance for several inches
of snow. For more details, see the long term discussion.

Long Term...Tuesday Night Through Monday

The main focus for the extended will be a passing clipper system
Tuesday night into Wednesday followed by much colder air
temperatures around the end of the week.

Snow Tuesday into Wednesday...
A strong clipper system is expected to cross into Wisconsin
Tuesday, bringing accumulating snowfall late Tuesday afternoon and
Tuesday evening. The timing/location for the heaviest snowfall
will likely be Tuesday evening in an area just north and east of
the upper low Tuesday evening, but this will likely be a
relatively narrow band compared to the overall snowfall. As a
result a widespread 3-4 inches seems likely with a narrower band
getting closer to 5-7 inches. As model certainty remains low on
the location of this higher band, maintained the watch over the
region this forecast issuance. Would expect the current Winter
Storm Watch covers more counties than will ultimately see a
warning, given the above info. On the backside of this system
Wednesday, expect strong cold air advection to continue snowfall
into Wednesday morning and stronger winds by the late morning to
afternoon period. Wind gusts up to 20 to 30 mph at times will
allow for some drifting snow in open areas during the day
Wednesday. Drier air will ultimately bring an end to the snow for
most Wednesday afternoon.

Cold...
Much colder air moves in behind this system, starting Wednesday
night through the early weekend. Overnight low temperatures will
see a downward trend from a few degrees above zero Wednesday night
to below zero across the whole area Friday and Saturday night.
Saturday high temperatures are expected to only be a few degrees
above zero for much of the area. Wind chills in the coldest parts
of the weekend may also reach as low as -10F to -30F at times.

&&

.AVIATION...for 18Z TAF Issuance
Issued at 1225 PM CST Mon Dec 8 2025

VFR conditions were the main flight category observed across the
region late this morning, with a few sites in central and north-
central WI reporting MVFR conditions at times due to passing
flurries. Anticipate these conditions will continue for the
remainder of the afternoon with intermittent flurries within the
lower cigs ahead of an approaching clipper system.

The quick-moving clipper system will bring accumulating snowfall,
reduced vsbys, and MVFR/IFR conditions to the area from west to
east late this evening into tonight. General arrival times at
CWA/AUW/RHI around 04z Tue, and around 05-07z Tue at the east-
central WI TAF sites. By early Tuesday morning, about 1-3 inches
of snow is forecast along and north of a Wausau to Appleton to
Manitowoc line. However, as the snow ends early Tuesday morning,
there are indications of the MVFR/IFR conditions sticking around
through the remainder of the TAF period with potential for
freezing drizzle to occur.

Southerly winds will increase this afternoon into this evening with
gusts to 15 to 20 kts. There still appears to be a period of LLWS
that will occur tonight with southwest winds up to 40 kts just
above the surface, before surface winds turn westerly by Tuesday
morning.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Winter Storm Watch from Tuesday afternoon through late Tuesday
night for WIZ018>021-030-031-035>037-045.

Winter Storm Watch from Tuesday evening through Wednesday
morning for WIZ022-038>040-048>050-074.
&&

$$

DISCUSSION.....Kruk/Uhlmann
AVIATION.......Kruk

NWS GRB Office Area Forecast Discussion