628
FXUS63 KGRB 231730
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
1230 PM CDT Wed Sep 23 2026

Forecast discussion for routine morning forecast issuance

.KEY MESSAGES...

- High pressure will bring dry weather to the region for the rest
  of the week.

- Next widespread rain chances arrive during the middle of next
  week.

&&

.DISCUSSION...
Issued at 1200 PM CDT Wed Sep 23 2026

After a cool start to the day, temperatures have risen into the
low 60s at most locations as of early this afternoon. A scattered
fair weather cu field has popped within the last couple of hours,
though conditions remain mostly sunny. Patchy fog may develop
late tonight into early Thursday morning as winds decouple and
skies clear out, though it remains uncertain whether or not it
will manifest as fog or low stratus.

No major changes to speak of from previous forecasts as Hudson Bay
high dominates the eastern CONUS. Persistence forecast more or
less continues as a result, with ensembles continuing to back off
on rain chances during the weekend. Long-range models attempt to
generate light rain over portions of central to north-central
Wisconsin Saturday afternoon as a weak shortwave traverses the
upper Mississippi Valley, though what little forcing and moisture
there is immediately dissolves upon hitting a barrier of dry air.
NBM probabilistic guidance shows only a 30 to 40% signal for
receiving 0.1" of QPF over our far western tier of counties
through Sunday morning. Another brief dry spell then settles in
through the early to middle part of next week.

Consensus holds that our next organized system moves through
sometime during the middle of next week as potent upper trough and
attendant surface low track through the upper Midwest. With PWATs
reaching 90th percentile relative to climo and more concrete
forcing present, initial thoughts point toward this being a heavy
stratiform rain setup. Will continue to monitor trends throughout
the week. Otherwise, temperatures will read mainly in the 60s
during the extended, occasionally warming into the low 70s.

&&

.AVIATION...for 18Z TAF Issuance
Issued at 1200 PM CDT Wed Sep 23 2026

MVFR cu field has begun lifting to VFR as of early this afternoon,
and should continue to scatter out over the next couple of hours.
Patchy fog may then develop late tonight into early Thursday
morning, bringing localized vsbys into IFR or even LIFR territory.
Opted not to include in the TAF due to low confidence on whether
it would materialize as fog or low stratus. VFR conditions then
prevail for the remainder of the TAF period, with mid and high
clouds passing over the area at times tomorrow.

Gusts to 15 knots will remain possible at all terminals through
this afternoon, with winds subsiding after sunset. Winds remain
under 10 knots through Thursday afternoon.

&&

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

&&

$$

DISCUSSION.....Goodin
AVIATION.......Goodin

NWS GRB Office Area Forecast Discussion