655
FXUS63 KGRB 021130
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
630 AM CDT Fri Oct 2 2026

Updated aviation portion for 12Z TAF issuance

.KEY MESSAGES...

- Areas of frost possible north of Hwy 29 late tonight into
  Saturday morning. A Frost Advisory has been issued.

- Frost will be possible at times across northern Wisconsin
  through early next week. Greatest chance for a widespread
  frost/freeze event will be Sunday night.

- Mainly dry through the middle of next week, with the exception
  of a 40 to 70% chance of showers over northern Wisconsin
  Saturday evening into Sunday morning.

&&

.DISCUSSION...
Issued at 100 AM CDT Fri Oct 2 2026

Frost/freeze potential... Frost/freeze setup on track for tonight,
continuing at times through early next week as cooler air
continues to filter in. Have blended in some NBM 10th percentile
to decrease lows for tonight by a degree or two with high sitting
overhead and decent window for clearing. NBM still showing healthy
signal (60 to 90+%) for lows below 33 degrees over north-central
into far northeast Wisconsin late tonight into Saturday morning,
though many of the CAMs are not as aggressive. Regardless, have
opted to throw out a Frost Advisory due to solid signal for under
36 degrees. Could potentially see a few counties being upgraded to
a Freeze Warning, though was hesitant to do so on this shift due
to the potential for increasing mid clouds mitigating temperatures
late tonight. Next chance for a more widespread frost/freeze
event then comes Sunday night into Monday morning, with
temperatures in the mid 30s even sneaking down toward the Fox
Valley. Expect additional headlines to be issued during this time.

Dry pattern ahead... Rain chances over the course of the extended
will be sparse at best, with our next chances for light rain
arriving Saturday evening. Transient shortwave energy will
accompany the passage of a clipper-like low over the upper Midwest
Saturday evening and night, generating isentropically forced
showers for areas mainly north of Hwy 29. However, abundance of
low level dry air will result in a meager 20 to 40% chance for
receiving 0.25" of QPF through Sunday morning. Otherwise, high
pressure will be the main driver of the synoptic pattern through
at least the middle of next week, bringing abnormally dry weather
from the Plains to the Midwest. This does not bode well for
northern Wisconsin where D2 (Severe) to D4 (Exceptional) drought
conditions exist. Next chances for more widespread rain don`t arrive
until Wednesday, though if this week is anything to go by, high
pressure could end up putting up a good fight.

&&

.AVIATION...for 12Z TAF Issuance
Issued at 600 AM CDT Fri Oct 2 2026

Clear skies and VFR conditions prevail this morning as high
pressure builds. FEW to SCT fair weather cu may develop over
northern Wisconsin this afternoon, though any lake clouds should
stay well north of RHI. Mid clouds then increase from the west
late tonight into Saturday morning.

Northwest winds should remain under 10 knots through this
afternoon, becoming light and variable tonight.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Frost Advisory from 11 PM this evening to 7 AM CDT Saturday for
WIZ005-010>013-018>021-073-074.
&&

$$

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

NWS GRB Office Area Forecast Discussion