NWS-Green Bay Forecast Discussion

						FXUS63 KGRB 271854
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
154 PM CDT Wed May 27 2026

Forecast discussion for routine afternoon forecast issuance

.KEY MESSAGES...

- Isolated to scattered thunderstorms are possible for the rest of
  the afternoon and early evening. A few storms could become
  strong to severe with damaging winds and hail, especially in
  central WI and the western Fox Valley between 4 pm and 8 pm.

- Conditions hazardous to small craft are expected tonight for
  the Lake Michigan nearshore waters south of Sturgeon Bay.
  Boaters should exercise caution on the bay of Green Bay this
  evening.

- There is a high risk for rip currents tonight for beaches along
  Lake Michigan in Manitowoc County.

- Mainly dry weather with above normal temperatures and low
  relative humidity for the next week, with highs mainly in the
  middle 70s to middle 80s.

&&

.DISCUSSION...
Issued at 153 PM CDT Wed May 27 2026

A back door cold front over northern WI will shift south across
the region this afternoon and early evening. Scattered showers
have already developed along the boundary. CAMs continue to show
thunderstorms initiating along the boundary by around 20z,
spreading south through the rest of afternoon, then exiting our
southern counties in the early evening. The arrival of cooler and
drier air behind the cold front and E-NE winds off Lake Michigan
will limit instability in northern and eastern WI, with better
instability (SBCAPE 1000-1500) expected over central WI and the
western Fox Valley. This is also the area where DCAPE calues are
currently highest (800-1000 j/kg). With Effective bulk shear
increasing to around 30 kts near the cold front, ingredients are
in place for a few strong to severe storms, especially in central
WI and the western Fox Valley. Damaging winds and hail will be the
primary threats.

The front should shift south of the region early this evening,
bringing a period of gusty northeast winds to the Fox Valley and
lakeshore areas, a period of high waves to our southernmost Lake
Michigan marine zones, and a high threat of rip currents for
Manitowoc County beaches. A Beach Hazards Statement has been
issued from this evening through early Thursday morning for
Manitowoc County.

Canadian high pressure and an Omega Block pattern will bring
a long stretch of mainly dry weather. Right now, only small
precipitation chances are expected with a back door cold front
late Sunday into Sunday night.

Ttemperatures will average well above normal through much of the
period, with highs mainly in the mid 70s to mid 80s. Low afternoon
relative humidity could lead to elevated fire weather conditions,
but green-up continues across northern WI and pine fuels have
become less volatile, so impacts may not be as significant as they
would have been a couple weeks ago.

&&

.AVIATION...for 18Z TAF Issuance
Issued at 1237 PM CDT Wed May 27 2026

A cold front was generating scattered showers across far northern
WI early this afternoon. As this front shifts south this
afternoon, showers and scattered thunderstorms will develop along
it. a few of the storms could become strong to severe, with
damaging winds and hail the primary threats. Most of this
activity should shift south of the region by early evening. Have
added TEMPO groups for storms at AUW/CWA/ATW, where the better
moisture and instability will be present, but only mentioned
Prob30 for the TAF sites farther north and east. After the storms
end, expect skies to clear.

As the front passes by early this evening, gusty northeast winds
are likely to develop for a 3-6 hour period. Gusts up to 25 kts
will be possible over the northeast WI terminals, especially at
KGRB and KMTW. The stronger gusts should subside overnight.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Beach Hazards Statement from 9 PM CDT this evening through late
tonight for WIZ050.
&&

$$

DISCUSSION.....Kieckbusch
AVIATION.......Kieckbusch