NWS-Green Bay Forecast Discussion

						FXUS63 KGRB 272358
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
658 PM CDT Mon Jul 27 2026

Updated aviation portion for 00Z TAF issuance

.KEY MESSAGES...

- Lingering heat indices are forecast into the upper 90s to low
  100s across central Wisconsin this afternoon and early evening.

- Gusty northerly winds will build waves from 3 to 5 feet on Lake
  Michigan south of Two Rivers this evening into Tuesday
  afternoon.

- Otherwise quiet conditions this week behind the active weather
  from today. Active weather potential will remain minimal until
  the end of the week.

&&

.DISCUSSION...
Issued at 247 PM CDT Mon Jul 27 2026

Much quieter conditions are expected to move into the region
behind the very active start to the day. Mean surface flow will
likely remain southerly through the afternoon, which will prolong
the heat impacts to central Wisconsin until the evening. A few
heat indices will likely continue to touch into the upper 90s to
lower 100s before winds shift over to the north overnight.

Quieter and much drier arrives tonight as winds pick up from the
north. Gusts up to 20 to 25 mph at times will help usher in a dry
and sunny day Tuesday as high pressure moves into the region.
Temperatures are expected to remain near or above normal on
Tuesday before warm air advection again increases through the
middle of the week. High temperatures on Thursday could get back
towards the middle to upper 80s and maybe even low 90s, which
could produce a few sporadic showers in the afternoon. Still, no
widespread active weather is expected until sometime Thursday
night into Friday with the next frontal passage. Rain and storms
then stick around Friday into early Saturday before some quieter
conditions return for the latter half of the weekend.

&&

.AVIATION...for 00Z TAF Issuance
Issued at 658 PM CDT Mon Jul 27 2026

Isolated showers or storms will continue for the next few hours,
staying just south/west of AUW/CWA. But will include a TEMPO group
at GRB/ATW/OSH/MTW as the activity drifts southward this evening.
Otherwise, dry conditions are expected the rest of the night into
Tuesday. Some high-end MVFR ceilings will continue this evening
with other VFR clouds around as well, then expect clearing skies
later tonight. Will be monitoring for fog development overnight,
especially across north-central WI, but have not included any
mention for now. Hazy skies are expected much of the TAF period as
elevated smoke remains over the region.

Winds will shift to the N/NNE this evening, with some gusts to
around 15 kts, with winds easing over central and north-central WI
overnight into Tuesday. Winds shift to the northeast across
eastern WI on Tuesday, gusting to 15 kts.

.KOSH...

A stray shower or storm is possible this evening, so will have a
TEMPO group to account for this threat as the activity sinks
south. Otherwise, dry conditions are expected. Some high-end MVFR
ceilings will be possible in/around any shower this evening with
other VFR clouds around as well, then expect clearing skies later
tonight. Hazy skies are expected much of the TAF period as
elevated smoke remains over the region. Winds will shift to the
N/NNE early this evening, with gusts to 15 kts, and continue into
Tuesday.

&&

.MARINE...
Issued at 247 PM CDT Mon Jul 27 2026

A tightening pressure gradient will cause northerly winds to
increase to 15 to 25 knots tonight into Tuesday. Waves will build
to 3 to 5 feet on the Lake Michigan nearshore waters south of Two
Rivers, and a Small Craft Advisory will be issued. Winds and waves
will gradually subside Tuesday afternoon as high pressure builds
in from the north.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 7 PM CDT this evening for WIZ035-036-045.
&&

$$

DISCUSSION.....Uhlmann
AVIATION.......Bersch
MARINE.........Uhlmann