051
FXUS63 KGRB 281743
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
1143 AM CST Sun Dec 28 2025

Updated aviation portion for 18Z TAF issuance

.KEY MESSAGES...

- Areas of fog expected today. Patchy freezing fog or freezing
  drizzle may create slippery conditions on untreated surfaces in
  northern Wisconsin this morning.

- Winter Storm Warnings are in effect for the entire forecast
  area, for heavy snow, strong winds and considerable blowing and
  drifting snow, from late this afternoon through Monday.
  Treacherous travel conditions are likely, and some tree damage
  and power outages are possible.

- Strong northwest winds gusting to 35 to 50 mph inland, and gale
  or storm force gusts to 45 to 50 knots on Lake Michigan, are
  anticipated from late tonight through Monday evening.

- A surge of below normal temperatures is likely towards the New
  Year`s time frame. Wind chills as cold as 10 to 20 below zero
  are possible Thursday morning and Friday morning.

&&

.DISCUSSION...
Issued at 416 AM CST Sun Dec 28 2025

Changes to Winter Storm Warning Headlines: Winter Storm Warnings
remain in effect for the entire forecast area, but some minor
changes to snowfall amounts and impacts have been made. In
general, snowfall amounts have come up a little bit and more
emphasis on potential power outages has been added, especially
in northern WI, where the heaviest snowfall will occur. Start
times have also been moved up a few hours in some places, as the
changeover to snow is expected to occur a bit quicker than
previously thought. Some minor adjustments to end times have also
been made, mainly to line up with decreasing trends in winds and
blowing snow.

Areas of fog covered the forecast area this morning, but rising
vsbys in central WI allowed for a cancellation of the Dense Fog
Advisory. Minor travel concerns were occurring over north central
WI, where air and road temperatures were hovering near freezing,
leading to potential for patchy icing due to freezing fog or
light freezing drizzle. Have covered the travel concerns with a
Special Weather Statement.

Low pressure was developing in eastern KS early this morning, as
a potent short-wave and jet streak ejected out of the base of the
deep Northern Plains upper trough. This low will deepen rapidly
as it moves through southern Lake Michigan this afternoon and
tracks toward southeast Ontario late tonight. Models continue to
trend higher with QPF/snowfall, so have bumped up snowfall totals
an inch or two, especially over our western and northern counties.
Strong winds gusting to 35 to 50 mph will produce considerable
blowing and drifting snow, and high-end gale to storm force gusts
are likely on Lake Michigan. Expecting 12 to 16 inches of snow
over parts of Vilas County (aided by lake-effect), 7 to 11 inches
across the rest of northern WI, and 4 to 7 inches farther south.
The combination of heavy snow accumulations and winds will likely
cause some tree damage and power outages, most notably over
northern WI and Door County. Most of the accumulating snow will
taper off late tonight into Monday morning, but winds are not
expected to decrease much until later in the day or evening, so
blowing and drifting snow will likely continue. Treacherous
travel conditions are likely through the event, but especially
tonight.

A clipper system passes north of the region Tuesday afternoon and
night, bringing a chance of snow followed by a surge of arctic
air for the New Year. This will bring renewed chances for lake-
effect snow in north central WI, as well as wind chills as low as
10 to 20 below zero later in the work week.

&&

.AVIATION...for 18Z TAF Issuance
Issued at 1142 AM CST Sun Dec 28 2025

Poor flying conditions are expected through the TAF period.

IFR/LIFR conditions to continue through today and tonight.

A potent low pressure system will bring a mix of rain and snow to
the region this afternoon. A transition to all snow will occur
from west to east as a cold front moves through in the late
afternoon and evening. The snow will become moderate to heavy at
times, especially over northern WI. LIFR/VLIFR vsbys will
accompany the heaviest snow. Plowing operations will be needed at
all area airports.

Behind the cold front winds will shift to the northwest and increase
tonight into Monday. Gusts of 30-40 knots will be possible late
tonight into Monday, resulting in considerable blowing and
drifting snow. LLWS will overspread the region tonight.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning from 3 PM this afternoon to 3 PM CST Monday
for WIZ005.

Winter Storm Warning from 3 PM this afternoon to noon CST Monday
for WIZ010-018-030-035-036.

Winter Storm Warning from 6 PM this evening to 3 PM CST Monday
for WIZ011>013.

Winter Storm Warning from 6 PM this evening to noon CST Monday
for WIZ019>021-031-037-045.

Blizzard Warning from midnight tonight to 9 AM CST Monday for
WIZ022.

Winter Storm Warning from 9 AM to 6 PM CST Monday for WIZ022.

Winter Storm Warning from 9 PM this evening to 3 PM CST Monday
for WIZ038-039-048-049-073-074.

Winter Storm Warning from midnight tonight to 6 PM CST Monday
for WIZ040-050.
&&

$$

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

NWS GRB Office Area Forecast Discussion