NWS-Green Bay Forecast Discussion

						FXUS63 KGRB 202325
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
625 PM CDT Mon Oct 20 2025

Updated aviation portion for 00Z TAF issuance

.KEY MESSAGES...

- Temperatures drop below normal Tuesday through Thursday, then
  return to near normal next weekend.

- Rain returns late this afternoon and evening, and continues
  through Tuesday. Periodic showers remain possible into Thursday.

- Blustery conditions anticipated through Wednesday, along with
  hazardous conditions for small craft on Lake Michigan.

&&

.DISCUSSION...
Issued at 154 PM CDT Mon Oct 20 2025

A cold front currently located over Minnesota, will track across
the region tonight. A line of showers ahead of the cold front will
arrive across central and north-central Wisconsin late this
afternoon and the rest of the area later this evening and
overnight. The showers will generally be light to moderate then
subsequently end from west to east late this evening and overnight
as the cold front tracks east.

After a brief break in the precipitation overnight, additional
showers will develop on Tuesday as an upper low tracks through the
western Great Lakes. Cyclonic WNW flow, additional short-waves
wrapping around the slowly departing upper low, and low pressure
tracking just northeast of the state (Tuesday night) will produce
periodic showers through midweek, along with blustery conditions
and below normal temperatures (highs in the 40s and lower 50s).
Scattered lake-effect showers may linger over north central WI and
northern Door County into Thursday.

High pressure brings drier conditions and near normal temperatures
for the end of the week and into the weekend.

&&

.AVIATION...for 00Z TAF Issuance
Issued at 624 PM CDT Mon Oct 20 2025

Clouds have begun to lower this evening, though conditions have
remained VFR. Radar shows a band of light to moderate rain
encroaching on our western sites, which will spread east and
become more widespread overnight. Rain chances will be accompanied
by MVFR cigs at most of the TAF sites. A brief break in the rain
followed by partial clearing in the Fox Valley then follows mid-
day on Tuesday, before another round of shortwave-driven precip
arrives later Tuesday afternoon. MVFR cigs will return to most of
the TAF sites during this time.

Brief window for LLWS develops early tonight as an 850 mb LLJ
passes over Wisconsin, before ending from west to east by around
06Z. Winds then continue to veer to westerly during the beginning
of the TAF period, ramping up late Tuesday morning as the
pressure gradient tightens up on the back edge of the departing
surface low. Surface gusts to 25 knots will be possible through
Wednesday morning.

&&

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

&&

$$

DISCUSSION.....Kurimski
AVIATION.......Goodin