NWS-Green Bay Forecast Discussion

						FXUS63 KGRB 202339
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
539 PM CST Thu Nov 20 2025

Updated aviation portion for 00Z TAF issuance

.KEY MESSAGES...

- Patchy fog, light rain, and drizzle continues through late this
  evening.

- Precipitation chances return late Monday through late
  Wednesday.

- Near normal to above normal temperatures expected through early
  next week, turning cooler (below normal) Wednesday into
  Thursday.

&&

.DISCUSSION...
Issued at 342 PM CST Thu Nov 20 2025

Tonight...Foggy and drizzly conditions under overcast skies
prevailed across the region for much of the day, ahead of an
approaching cold front. This cold front is expected to sweep
southeast across the area between late this afternoon through late
this evening. Given upstream observations and radar imagery
indicated light rain was falling along the front, decided to include
low chance PoPs (15-20%) across the area this evening. The front
will also push the fog out of the area upon arrival. Clearing skies
will be a bit delayed following the frontal passage, potentially not
clearing until Friday morning. Given the uncertainty in clearing,
increased low temperatures by a degree or two with values ranging
from the mid 20s to low 30s.

Rest of the forecast...Surface high pressure moves into the region
for Friday into Saturday, keeping conditions dry. A shortwave and
weak cold front look to move across Upper Mississippi Valley
Saturday into Saturday night, but the main shortwave should stay far
enough north to limit precip potential for the forecast area. High
pressure moves back into the region Sunday into Monday, bringing the
return of dry weather. Long-range models indicate the next chance
for precip will be sometime from Monday night through Wednesday, and
possibly lingering into Thursday. The first feature of interest is
the remnants of an upper-level low/trough lifting into the region
late Monday into Tuesday from the southwest U.S., with another
upper-level low/trough from the Northern Plains late Tuesday into
Wednesday. P-type with the first part appears to be rain as
warmer air will prevail; the second part looks to have more of a
wintry mix due to colder air dropping into the area from Canada.

&&

.AVIATION...for 00Z TAF Issuance
Issued at 538 PM CST Thu Nov 20 2025

Low ceilings and patchy fog will make for IFR conditions across
most TAF sites this evening. Some improvement is expected as we
get into the overnight period as a weak cold front brings in drier
air for the low levels, with some MVFR ceilings visible upstream
on satellite and clearing likely to follow sometime Friday
morning. Therefore, expect gradual, but slow improvement in the
flying conditions through the overnight period, with MVFR in most
locations early Friday morning and then good flying conditions by
Friday afternoon.

&&

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

&&

$$

DISCUSSION.....Kruk
AVIATION.......Uhlmann