681
FXUS63 KGRB 190651
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
151 AM CDT Wed Aug 19 2026

Forecast discussion for routine morning forecast issuance

.KEY MESSAGES...

- Some early morning patchy fog, otherwise quiet weather today,
  then showers and a few storms arrive Thursday afternoon into
  Friday (50-80% chance). A drought busting rain is not expected.

- High temps remain near seasonal norms into the weekend with a
  few cool nights across northern WI.

&&

.DISCUSSION...
Issued at 151 AM CDT Wed Aug 19 2026

Shower/Storm Potential...Next round of organized showers and
storms arrives Thursday into Friday (50-80% chance), as a cold
front and shortwave drop across the state. Initial WAA precip
could arrive late Thursday morning or early afternoon across north
central WI, but higher chances for rain hold off until Thursday
night. Another round of showers/storms is expected on Friday,
especially over eastern WI, as the front crosses the region.
Locally heavy rainfall will be possible with any storm as PWATs
climb to ~1.5" and soundings showing tall/skinny CAPE. However,
this won`t be a drought buster type of event and some spots may
miss out on any appreciable rain. Widespread severe weather is not
expected Thursday night as better instability/forcing remains to
our west. Will need to watch Friday afternoon if the front slows
down a little and we can destabilize, as dewpoints will climb
into the mid to possibly upper 60s ahead of the front. Lingering
showers are possible this weekend as northwest flow sets up across
the Great Lakes. The next chance for showers and storms arrives
early next week with the arrival of another low pressure system
and cold front.

Fog Potential...Light winds and clearing skies will lead to some
patchy fog development across portions of the area early this
morning, especially where the heavier rain fell last evening. The
fog could be dense in a few spots. The fog will linger through
sunrise then burn off. The drier air should hold off fog
development tonight.

Temps & Humidity Levels...High temps will remain pretty close to
seasonal norms this week and into the weekend with highs mainly
in the mid 70s to low 80s. Some cool August nights are expected
across northern WI tonight and again this weekend with lows mainly
in the 40s, with a few upper 30s in the typical cold spots
possible. Less humid air arrives today as dewpoints drop into the
upper 30s to low 50s. Humidity levels will climb on Friday as the
next system moves across the region, then drop off slightly for
the weekend.

&&

.AVIATION...for 06Z TAF Issuance
Issued at 1035 PM CDT Tue Aug 18 2026

Showers have gradually come to an end across the forecast area
late this evening as a cold front continues to sink south,
leaving clearing skies and VFR conditions in their wake. More
stable air then filters in behind the front on Wednesday, leaving
us with a fair weather cu field at around 5 to 7k ft developing a
couple hours after daybreak.

CAMs still showing a signal for patchy fog developing overnight,
though would likely be limited to areas that recently received
rainfall. Have retained VFR vsbys for this TAF issuance due to
uncertainty of fog coverage.

Northwest winds gusting to 15 knots will be possible during the
first couple hours of the TAF period, eventually subsiding to
light and variable overnight.

&&

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

&&

$$

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

NWS GRB Office Area Forecast Discussion