NWS-Green Bay Forecast Discussion

						FXUS63 KGRB 191255
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
655 AM CST Wed Nov 19 2025

New Information added to update section

.UPDATE...
Issued at 653 AM CST Wed Nov 19 2025

Cancelled the Dense Fog Advisory for Shawano and Waupaca counties.
There has been improvement in vsbys in many other counties, but
suspect there are pockets of dense fog/poor vsbys in most of the
remaining counties. Satellite is being masked by high clouds, so
don't have a good of a view of the fog/stratus coverage anymore.

&&

.KEY MESSAGES...

- Areas of dense fog will result in hazardous travel conditions
  for the morning commute across parts of north central, central
  and east central Wisconsin. A Dense Fog Advisory is in effect.

- Patchy light rain, possibly briefly mixed with light snow or
  light freezing rain, across northern Wisconsin late tonight
  into early Thursday morning.

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

&&

.DISCUSSION...
Issued at 346 AM CST Wed Nov 19 2025

Have expanded the Dense Fog Advisory into Lincoln and Langlade
counties in north central WI, and Manitowoc County in east
central WI. Also extended the expiration to 15z/Wed. Fog is
patchy across parts of the advisory area, but did not remove any
counties, as fog will probably fill in a bit toward sunrise.
Satellite/observations/web cams showed the worst conditions
occurring in the Fox Valley (including the Hwy 41 corridor from
Green Bay to Oshkosh) and the Wisconsin River Valley (including
Hwy 39/51 from Portage County north into Lincoln County). Fog and
low stratus was starting to work its way into the western parts of
Oneida/Vilas counties, so will need to watch trends there for
possible headline expansion.

The fog should mix out by mid-morning, followed by increasing high
clouds. A large area of low clouds situated southwest of the
forecast area will start to work its way into the southwest part
of the forecast area late in the day. High temperatures will be in
the upper 30s and lower 40s.

A weak cold front and low-amplitude short-wave will approach the
forecast area late tonight, then move through Thursday into
Thursday evening. This looks to be another moisture-starved
system, with the best saturation occurring across far northern WI.
Will only carry chance pops across northern WI, though some
neighboring offices feel enough low-level saturation will occur
for some drizzle farther south. Have kept the mention of drizzle
out of the forecast for now, as timesections don't show much (if
any) lift in the saturated layer. Precipitation type across
northern WI should be mainly rain, as 1000-850 mb thicknesses
remain above 1300 meters. However, with surface/boundary layer
temperatures close to freezing, cannot rule out spotty light
freezing rain or snow late tonight/early Thursday.

Rest of the forecast: Split flow is expected through the period,
with the forecast area firmly enternched in dry northern stream
zonal flow. A weak system passes well north of the region over the
weekend, with any precipitation staying to our north. The
remnants of the southern stream upper low kicks northeast toward
the Great Lakes during the middle of next week, and this could
bring a chance of precipitation. Overall, expect below normal
precipitation and seasonable temperatures through the week.

&&

.AVIATION...for 12Z TAF Issuance
Issued at 530 AM CST Wed Nov 19 2025

Areas of dense fog continued across parts of north central,
central and east central WI early this morning, and should linger
until around 15z. After the fog mixes out, mainly high clouds will
prevail until late in the day, when low clouds will work their way
back into central WI. The low clouds will spread northeast,
reaching the TAF sites between 01z-04z, with flight conditions
dropping to MVFR/IFR over much of the area overnight. A weak cold
front will approach the region late tonight, and may produce
scattered light rain/snow at the RHI TAF site toward the end of
the TAF period. Patchy fog will also develop in NC/C WI overnight,
but visibilities should not be nearly as low as this morning.

Light and variable winds will become S-SW 5 to 10 knots this
afternoon and tonight.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory until 9 AM CST this morning for WIZ018-019-
030-035-036-038-039-045-048>050.
&&

$$

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