107
FXUS63 KGRB 221742
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
1242 PM CDT Wed Jul 22 2026

Updated aviation portion for 18Z TAF issuance

.KEY MESSAGES...

- Tranquil and comfortable weather returns today through Friday.

- Warmer temperatures and higher humidity return over the weekend,
  with high temperatures climbing into the upper 80s to near 90
  and heat indices reaching into the 90s.

- Periodic chances for thunderstorms return Saturday through
  early next week, though timing, coverage, and severe weather
  potential remain uncertain.

&&

.DISCUSSION...
Issued at 1200 PM CDT Wed Jul 22 2026

Today through Friday...

High pressure in southern MN will slide southeast today and
gradually slide east across the southern Great Lakes region
tonight through Thursday. The core of the surface high will
shift to the NE US but the high pressure will extend much
further west across WI. In the upper levels we will remain in
between the ridge to the west and trough to the east. While
there should be some activity aloft with various shortwaves the
conditions will be much too dry for anything to come of the
upper level forcing.

The high pressure will finally start to exit Friday with lower
pressure pushing in from the west as the ridge aloft nudges
toward the region. No real weather concerns for this period as
we remain dry.

Friday night through Wednesday...

As the ridge slides into the region this weekend expect
temperatures to warm back up with a return of humid conditions,
but also a return of precip/storm chances. Saturday will carry
minor chances across northern WI late Friday night into the day
Saturday with a weak embedded shortwave sliding down the ridge.
There currently looks to be enough moisture and forcing to bring
some precip with some instability in the region likely allowing
for some storms as well. While timing is not exactly great for
stronger storms there is enough shear present to perhaps bring a
few stronger storms so its worth monitoring.

Sunday and Monday will be warmer with highs in the upper 80s to
low 90s with multiple chances for storms though the best chance
for strong to severe storms appears to be Sunday
afternoon/evening where WAA and a warm front as the primary
forcing should allow for high instability and a decent LLJ will
bring in enough shear to bring some severe weather concerns.
Otherwise increased uncertainty into early next week but
eventually we will see a front push through and cool the region
off a tad but since the ridge remains in place we should
continue to expect warm conditions. Later next week the ridge
may revert back west a bit and allow .

It is worth mentioning that Beach Hazards Statement may be
needed for Friday as breezy onshore winds may yield nearshore
wave heights from 3-5 feet.

&&

.AVIATION...for 18Z TAF Issuance
Issued at 1241 PM CDT Wed Jul 22 2026

High pressure stays in place through Thursday. Fair weather VFR
cumulus through late afternoon, then clear skies tonight into
Thursday morning. Another round of mainly scattered fair weather
VFR cu Thursday afternoon. Winds will be NW less than 10 kts this
afternoon, becoming light W/SW tonight into Thursday.

Outlook...VFR conditions will persist through Friday under dry
high pressure. Thunderstorm potential returns over the weekend,
mainly late Saturday through Sunday.

.KOSH...
Scatterd to broken fair weather cumulus (060-080) through late
this afternoon, then skies clear tonight. Thursday starts off
clear, but another round of scattered fair weather cu will develop
by Thursday afternoon.

Winds up to 10 kts could briefly veer to NNE next few hours, but
overall will be from the NW the rest of the afternoon. Gusts could
reach 13-15 kts, but they will not be near as frequent as what
occurred on Monday or Tuesday. Light winds tonight will be from
the W, then winds on Thursday will increase to 5-10 kts from the
WSW by late morning and last through the afternoon.

&&

.MARINE...
Issued at 1200 PM CDT Wed Jul 22 2026

Lighter winds and lower waves have returned to our marine zones
as higher pressure has nudged into the region behind the
departed low pressure system. Winds will remain light in the
waters for much of the next couple days though there will be a
brief period of higher winds on the northeast side of Lake
Michigan which may allow for a couple hours of Small Craft
thresholds over the area. However, there is a better chance into
Friday afternoon as lower pressure begins to impinge on the high
pressure that will increase the pressure gradient over the north
lake and thus a longer period (6-12hrs) of Small Craft
conditions are expected at this.

&&

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

&&

$$

DISCUSSION.....AK
AVIATION.......JLA
MARINE.........AK