183
FXUS63 KGRB 130856
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
356 AM CDT Mon Oct 13 2025

Forecast discussion for routine morning forecast issuance

.KEY MESSAGES...

- Above average temperatures continue today, but a chilly night
  expected. Cooler, but still near normal, readings for Tuesday
  and Wednesday, with a warm up for late in the week.

- Light rain ending this morning (under 0.10"). Additional rain
  chances Tuesday evening/night and again at times later this
  week and into the weekend.

&&

.DISCUSSION...
Issued at 356 AM CDT Mon Oct 13 2025

Rain Chances & Cloud Trends: Line of showers continues to move
east across the area early this morning, ahead of a decaying
frontal boundary. A secondary line is trying to form behind the
main line, but should be more isolated. These lines will continue
eastward and exit far eastern WI by ~18z, except a little later
possibly for Door Co. Additional rain amounts look to remain under
0.10" for most spots. As the showers exit, look for sunshine to
return for the rest of the day. High clouds will begin to increase
towards the evening and continue into tonight/Tuesday. An omega
block will attempt to set up over the CONUS by mid-week, with
ridging building the Plains and western Great Lakes. However, a
shortwave is expected to ride the west/northeast flow Tuesday
into early Wednesday, which could bring showers/sprinkles to the
area, especially along and south of Hwy 29. Then as the ridging
builds over the region, a dry stretch of weather is expected mid-
week, before additional weak shortwaves will bring chances for
showers late in the week. A larger system and associated cold
front will likely bring higher chances for rain late Friday into
Saturday, but timing/strength issues still need to be ironed out
by the models.

Temperatures & Possible Frost/Freeze: Once we get rid of the
showers/clouds, the delayed CAA, sunshine and downsloping winds
will allow temps to quickly climb in the late morning and
afternoon. Most spots should get into the mid 60s to around 70,
with slightly cooler readings in far north central WI. Clear skies
and diminishing wind will allow temps to fall quickly in the
evening, with a chilly night on tap for most of the region. MET
guidance quite a bit colder across central and north central WI,
with many spots in the 20s. Have leaned colder where the lighter
winds are expected over the west, but did not go as cold as the
MET. May end of needing a Frost Advisory for portions of central
WI, where the growing season has not officially ended. The
stronger push of CAA arrives on Tuesday into Wednesday, which will
bring a return of near normal temps in the 50s to around 60. Temps
look to climb back to above normal late in the week.

&&

.AVIATION...for 06Z TAF Issuance
Issued at 1046 PM CDT Sun Oct 12 2025

Scattered light showers ahead of a cold front will shift across
the area overnight. Showers will end before daybreak Monday over
central WI, and from the Fox Valley to the lakeshore by mid
morning. Rainfall amounts at any location will be light.
Conditions will mainly be VFR, except for a brief interlude of
MVFR cigs late tonight into Monday morning for portions of central
to north-central WI (mainly RHI).

Southeast winds veer south late tonight, gusting to around 20
kts at times. 40-50 kt low-level jet crossing the area will also
result in LLWS at all TAF sites through late tonight. As the rain
ends with the passage of the cold front Monday morning, winds will
become light out of the northwest.

&&

.MARINE...
Issued at 356 AM CDT Mon Oct 13 2025

persistent south/southeast winds will continue to slowly
increase waves on Lake Michigan early this morning, but wave
heights at the mid-lake buoy and the buoy off of Two Creeks are
still around 2.5 to 3.5 ft. Latest wave model guidance is still
running a little high, but still expecting some 4 footers north
of Sturgeon Bay through ~12z, so will keep the Small Craft
Advisory going there, but trim back the timing to end at 12z, and
cancel south of there. A period of persistent/gusty southeast to
south winds is expected Thursday evening into Saturday morning,
which will build waves on Lake Michigan.

&&

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

&&

$$

DISCUSSION.....Bersch
AVIATION.......JLA
MARINE.........Bersch