839
FXUS63 KGRB 181137
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
537 AM CST Tue Nov 18 2025

Updated aviation portion for 12Z TAF issuance

.KEY MESSAGES...

- Light to moderate snow in central Wisconsin today, with
  accumulations of 1 to 3 inches expected west of the Fox Valley.
  A Winter Weather Advisory is in effect for Wood, Portage,
  Waupaca and Waushara counties until noon.

- Less than an inch of snow expected from the Fox Valley to
  Manitowoc County.

- Seasonal temperatures with below normal precipitation for the
  rest of the week.

&&

.DISCUSSION...
Issued at 346 AM CST Tue Nov 18 2025

No changes to the ongoing winter weather headlines.

A frontogenetic band of precipitation was just moving into the
far southwest part of the forecast area at issuance time. The
regional radar mosaic showed that the northward push of the band
had just about ended to our west, suggesting that it will set up a
little farther south than was previously expected. Most of the
meso-models have caught on to this, and don`t expand the
precipitation farther north than our southern two rows of
counties. Though most observations to our south have shown rain
early this morning, colder surface wet bulb temperatures in
central and east central WI should result in a fairly quick
changeover to snow. Have adjusted pops/QPF/snowfall accordingly,
which focuses most of the accumulation over southern Wood,
southwest Portage and Waushara counties (roughly the south half of
the advisory area). Considered whether or not the advisory needed
to be expanded east into Winnebago County, but decided against
it. Boundary layer temperatures/wet bulbs were warmer near Lake
Winnebago early this morning, and east winds during the day will
likely keep them milder, which should limit accumulation to an
inch or less. As such, there have been no changes to the Winter
Weather Advisory. An upper low will track through Illinois this
afternoon, and the deformation zone of this feature will continue
to produce light snow or mixed rain/snow over C/EC WI until mid to
late afternoon.

Rest of the forecast: Zonal flow aloft will bring a couple quick-
moving and moisture deficient systems through the region Wednesday
night into Thursday and Saturday into Saturday night. Precipitation
chances are fairly low, and mainly focused over northern WI.
Seasonable temperatures are also anticipated.

&&

.AVIATION...for 12Z TAF Issuance
Issued at 526 AM CST Tue Nov 18 2025

Ceilings and vsbys will lower this morning as snow or mixed
rain/snow overspreads central and east central WI. Conditions
will deteriorate to IFR/MVFR where the precipitation is steadiest
and heaviest. Farther north, mainly mid/high clouds are
anticipated. Precipitation ends mid to late afternoon, followed by
clearing skies regionwide. Winds will be light from the east
today, then light and variable tonight.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until noon CST today for WIZ035>037-045.
&&

$$

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