900
FXUS63 KGRB 172000
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
200 PM CST Mon Nov 17 2025

Forecast discussion for routine afternoon forecast issuance

.KEY MESSAGES...

- Light to moderate snow late tonight into Tuesday morning across
  the south with accumulations of 1 to 3 inches. A Winter Weather
  Advisory has been issued for central Wisconsin west of the Fox
  Valley.

- The Fox Valley could see up to an inch of snow with lesser
  amounts across the rest of central Wisconsin not in the advisory
  and east-central Wisconsin. North-central and northeast
  Wisconsin will be mainly dry.

- Another low pressure system will bring precip chances (30-60%)
  Thursday, mainly in the form of rain.

- Temperatures remain pretty seasonal through the week.

&&

.DISCUSSION...
Issued at 150 PM CST Mon Nov 17 2025

Snowfall amounts tonight into Tuesday: Models have come into
better agreement and made a shift to the north with the band of
FGEN late tonight into Tuesday morning. In addition, the hi-res
models are now sampling this system and are coming into better
agreement with the northward shift. HREF probabilities of
exceeding 1 inch of snow is now around 50% across the Fox Valley
from Appleton south to Oshkosh with 70-80% west of this area. The
following probabilities are currently progged across central
Wisconsin west of Appleton and Oshkosh and south of Marshfield
late tonight into Tuesday morning:

- 50-70% of exceeding 2 inches
- 30-50% of exceeding 3 inches
- 10-30% of exceeding 4 inches

Given these probabilities the most likely snowfall amounts across
this area is expected to be 1 to 3 inches, with snowfall amounts
up to 4 inches possible (75th percentile) and the worst case
scenario of 5 inches (90th percentile). The timing of this snow,
during the morning commute on Tuesday, adds a layer of complexity
as the impact will likely be higher even if snowfall amounts come
in on the lower end. Given the impacts of the first accumulating
snow of the season during the morning commute will issue a Winter
Weather Advisory for Waushara, Wood, Portage, and Waupaca counties
from late tonight through Tuesday morning. The compact nature of
frontogenesis means snowfall amounts will be in a tight gradient
with southern portions of Wood, Portage, and Waupaca counties
likely receiving more snow than the northern portion of those
counties.

The rest of the forecast area will range from completely dry
across north-central Wisconsin, to a mix of rain and snow across
east-central Wisconsin north and east of the Fox Vally and some
light snow across central Wisconsin north of the main FGEN band.
Snowfall amounts outside of the main band are expected to mainly
be below an inch given abundant dry air in place and the lack of
forcing.

Rest of the forecast: Dry conditions will prevail on Wednesday as
high pressure drifts over the Great Lakes. Next chance (40-70%)
for precip arrives Thursday as a clipper-like system races across
southern Canada. While the best moisture and dynamics will be
north of the area, some WAA, a shortwave trough, along with a weak
frontal boundary, will move across the area to produce some
precip. Amounts are looking on the light side, with probabilities
of 0.25"+ under 25%. Looking like mainly rain, but a little snow
could mix in over the north. Ensembles have really backed off on
bringing a more moisture rich, wrapped-up system for Friday into
Saturday, so unfortunately prospects for any substantial rain now
looks low.

Temperatures & Winds: Temps will remain pretty close to normal
for the first half of the week, with highs mainly in the upper
30s to mid 40s and lows in the upper teens and 20s (slightly
warmer near Lake Michigan). A brief shot WAA will give a small
bump in temps on Thursday with highs in the mid and upper 40s for
most locations. We could get a 50 in the south, but probabilities
of reaching 50 remain under 20% due to cloud cover. Winds will be
much lighter today and for the majority of the week, with gusts
only reaching up to 15 mph.

&&

.AVIATION...for 18Z TAF Issuance
Issued at 1118 AM CST Mon Nov 17 2025

VFR conditions are expected through tonight with light winds and
some high clouds drifting across the region at times. Lower clouds
and some flurries will be approaching ATW by ~12z Tuesday as the
next weather maker approaches. This system will bring light snow
(possibly mixed with a little rain) to portions of central and
east-central WI Tuesday morning, especially along and south of Hwy
10, after 12z. Conditions will fall to MVFR and IFR with the main
snow band, with the lowest conditions expected south of ATW and
CWA.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from 2 AM to noon CST Tuesday for
WIZ035>037-045.
&&

$$

DISCUSSION.....Kurimski
AVIATION.......Kurimski