269
FXUS63 KGRB 060703
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
203 AM CDT Tue Oct 6 2026

Forecast discussion for routine morning forecast issuance

.KEY MESSAGES...

- Light rain showers will move across the area this morning.

- Breezy south-southwest winds gusting 25 to 35 mph are expected
  to create hazardous marine conditions this morning through early
  Wednesday morning.

- Patchy frost will be possible over northern Wisconsin Thursday
  night into Friday morning with low temperatures in the mid 30s.

&&

.DISCUSSION...
Issued at 203 AM CDT Tue Oct 6 2026

Today...Ahead of an expected cold frontal passage later this
evening/night, scattered rain showers prevailed across the region
early this morning driven by a 700-850mb jet and WAA. These showers
were high-based and falling from a shallow saturated layer, which
will keep QPF amounts low of up to 0.10 inches. NBM probs indicating
the highest probs for 0.10 inches in 24 hrs is 30-45% for locations
mainly north of Highway 29. The showers will exit to the east by mid-
morning. Following the showers, a tightening surface pressure
gradient ahead of the cold front will result in gusty
south/southwest winds at the surface. Forecast soundings indicate
mixing to at least 925mb where winds of 25-30kts look to mix to the
surface, producing surface wind gusts of 30-35mph. If deeper mixing
can occur to 850mb, a few surface gusts up to 40 mph cannot be ruled
out, mainly in far eastern WI. Surface winds will subside this
evening before the cold front moves across the area from the
northwest. High temperatures will be about 10 degrees above normal,
warming into the low to mid 70s. A few CAMs indicate pre-frontal
isolated showers developing this evening, however the front appears
to be moisture starved, so anticipate conditions will remain dry.

Rest of the Forecast...Quiet, cooler, and dry conditions are
expected through at least Friday as high pressure resides over the
area. This will present result in a few chilly mornings, with the
potential for frost development Friday morning. NBM probs for Friday
morning`s temperatures falling below 37 degrees show values of 40-
60% for locations mainly north of Highway 29, with some spots in
central WI up to 25%. The high pressure will depart on Friday,
allowing southerly return flow to cause temperatures to rebound into
the weekend with highs climbing into the mid 70s, and potentially
upper 70s on Sunday. The next chance for precipitation is rather
muddled for the weekend due to a potential tropical disturbance in
the Gulf. However, there are some indications of rain Friday night,
but there is little agreement in this solution.

&&

.AVIATION...for 06Z TAF Issuance
Issued at 1041 PM CDT Mon Oct 5 2026

A band of showers is expected to exit northeast WI a few hours
after 06z. Despite the rain, VFR conditions will prevail
overnight. The main story continues to be the winds. Low level
wind shear should develop after 08z and continue into Tuesday
morning before surface winds pickup by mid to late morning. Gusts
of 25 to 34 knots will be possible Tuesday afternoon, with the
highest gusts over eastern Wisconsin. Surface winds should ease
late Tuesday afternoon and evening, with areas of low level wind
shear at times throughout the evening. Surface winds will also
veer to the west and then northwest Tuesday night.

&&

.MARINE...
Issued at 203 AM CDT Tue Oct 6 2026

Southerly winds will quickly increase this morning to 15 to
25 knots with gusts to 30 knots. This will cause waves to build to 3
to 5 ft on Green Bay and 5 to 9 feet on Lake Michigan. The forecast
trend continues with winds looking to remain below Gale Warning
criteria, but cannot rule out a few gale force gusts, mainly near
Washington Island. Winds and waves will subside on the Bay mid-
evening, and subside on the nearshore waters gradually after
midnight. No changes were made to the Small Craft Advisories in
effect.

&&

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

&&

$$

DISCUSSION.....Kruk
AVIATION.......Eckberg
MARINE.........Kruk

NWS GRB Office Area Forecast Discussion