497
FXUS63 KGRB 242310
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
610 PM CDT Sun Aug 24 2025

Updated aviation portion for 00Z TAF issuance

.KEY MESSAGES...

- First glimpse of early fall expected early this week with cooler
  temperatures. Patchy frost possible in north central Wisconsin
  late Monday night.

- Some waterspouts are possible through tonight across the bay of
  Green Bay and Lake Michigan.

- Next chance of rain arrives Wednesday night into Thursday.

- Labor Day weekend weather is looking good.

&&

.DISCUSSION...
Issued at 326 PM CDT Sun Aug 24 2025

Am initial short-wave, and associated showers and storms, was
shifting east of the region, while another weaker short-wave was
bringing additional showers into the region this afternoon. Expect
the showers to wane as the second wave departs later this
afternoon/toward sunset. Clouds will be persistent in some areas
this evening, but clearing should arrive regionwide overnight.

The pattern remains favorable for waterspouts for most of tonight,
though convective cloud depths become less favorable late tonight
into Monday. Have removed the slight chance of waterspouts beyond
09z/Mon. So far, we have not received any reports of waterspouts
today.

Dry weather and a gradual moderating trend in temperatures is
anticipated from Monday through Wednesday. Early fall-like
temperatures should return to normal by mid-week. Still seeing
potential for frost development in north central WI late Monday
night, with lows dropping into the middle to upper 30s. Less
confident in chances Tuesday night, as the Canadian surface high
will be dropping south, with an increasing pressure gradient
setting up over northern WI. Gusty west winds will develop on
Wednesday as this gradient shifts south.

A back door cold front will sag south through the area Wednesday
night into Thursday and bring a small chance of showers and
thunderstorms. Blended model pops have finally caught on to this
trend. A brief and minor cool down will occur behind the front.

An initial look at next weekend supports mostly dry conditions
setting up, along with pleasant temperatures hovering near normal
for this time of year.

&&

.AVIATION...for 00Z TAF Issuance
Issued at 610 PM CDT Sun Aug 24 2025

A deck of mostly VFR stratocumulus clouds continues to pivot over the
region late this afternoon. There is a pocket of MVFR based clouds
over the higher terrain regions of central and north-central WI.
Clouds should begin to scatter out this evening as low-level
instability wanes, however, with a fairly expansive cloud deck
currently in place it may take several hours for skies to become
mostly clear.

Monday another VFR cumulus field is expected to develop mid to late
morning and linger through the afternoon. However, with a drier
airmass moving into the region don`t expect the cu to be as
expansive as the past few days. Northwest winds won`t be quite as
breezy Monday, but gusts may peak at 15-20 kts during the
afternoon.

&&

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

&&

$$

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