466
FXUS63 KGRB 192033
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
233 PM CST Wed Nov 19 2025

Forecast discussion for routine afternoon forecast issuance

.KEY MESSAGES...

- A light wintry mix could cause a few slick spots to develop on
  area roads across far northern Wisconsin late tonight into early
  Thursday morning.

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

&&

.DISCUSSION...
Issued at 233 PM CST Wed Nov 19 2025

The latest RAP analysis and satellite/radar imagery show high
pressure centered over the Great Lakes early this afternoon.
Upstream, a cold front over the western Dakotas is moving east,
with showers pushing into northern Minnesota and western Lake
Superior within a region of mid-level warm advection. Widespread
low stratus is evident in the warm advection pattern ahead of the
cold front across Minnesota and Iowa. Forecast concerns revolve
around light precipitation chances tonight into Thursday,
including the potential for freezing drizzle or rain across the
north, and fog potential tonight.

Tonight and Thursday:
As high pressure exits to the east, warm advection will increase
across the region tonight. The large area of stratus upstream is
forecast to move from southwest to northeast across the area this
evening. Forecast soundings show saturation increasing from the
ground up and also the top down, but a wedge of dry air persists
between 5000 and 10000 ft. This moisture profile suggests a lack
of ice crystals in the cloud bearing layer, introducing the
potential for drizzle or freezing drizzle. Additionally, the
chance of showers will increase across far northern Wisconsin
after midnight. With surface temperatures hovering right around
the freezing point, light snow, freezing drizzle, or freezing rain
cannot be ruled out given the saturation issues. While the chance
of freezing precipitation is low, impacts would be primarily
limited to untreated surfaces, bridges, and overpasses, but trends
will be monitored closely. Further south, the saturation depth
appears too shallow for drizzle until the pre-dawn hours when
forecast soundings indicate saturation folding over the top of the
low- level inversion.

Regarding fog potential, patchy to areas of fog are expected to
develop over central and north-central Wisconsin tonight. However,
given the advection of stratus aloft, radiational cooling
conditions will not be as ideal as previous nights, which should
prevent the fog from becoming as widespread or dense as last
night. Lows should occur this evening or early overnight in the
upper 20s to middle 30s.

The chance of showers across the north will mostly depart by late
morning to midday on Thursday. However, the chance of drizzle may
persist through the middle of the afternoon under overcast
conditions. Highs on Thursday are expected to range from the lower
to upper 40s.

Long Term (Thursday Night through Tuesday):
A split flow pattern will continue across the Lower 48 over the
next week. While shortwave energy generally meanders over the
Desert Southwest, the northern stream will remain more progressive
and low amplitude, having the most influence on local weather. In
general, low impact weather will be present in this pattern over
the next week. A weak, moisture-starved system is forecast to pass
well north of the region over the weekend, keeping any significant
precipitation to our north. By the middle of next week, the
remnants of the southern stream upper low are expected to kick
northeast toward the center of the country. This could bring a
chance of precipitation to the region around Tuesday or Wednesday.
Overall, expect below normal precipitation and temperatures near
to slightly above normal through the week.

&&

.AVIATION...for 18Z TAF Issuance
Issued at 1124 AM CST Wed Nov 19 2025

High pressure will slide east this afternoon, allowing VFR
conditions with passing mid and high clouds to persist through
early evening. Winds will remain south to southwest at 5 to 10
kts.

Conditions are expected to deteriorate tonight as low-level
moisture returns ahead of an approaching cold front. MVFR/IFR
ceilings are forecast to overspread the region from 01z to 05z.
The poorest conditions are expected across north-central WI
(RHI/CWA/AUW), where ceilings will likely fall to LIFR/IFR levels
with visibilities dropping to MVFR/IFR in mist. Scattered light
rain or mixed precipitation is possible at RHI late tonight into
Thursday morning and kept the prob30 from 09Z-15Z.

Further east across the Fox Valley and lakeshore (GRB/ATW/MTW),
ceilings will lower to MVFR late tonight, but visibilities should
largely remain VFR. Improvement will be slow on Thursday morning,
with IFR/MVFR ceilings lingering through 15z-17z.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION.....MPC
AVIATION.......MPC