NWS-Green Bay Forecast Discussion

						FXUS63 KGRB 271059
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
559 AM CDT Tue Oct 27 2026

Updated aviation portion for 12Z TAF issuance

.KEY MESSAGES...

- Rain (30-50% chance) today, highest over north-central WI. More
  rain likely (50-90%) and the chance (15-30%) for a few non-
  severe storms Wednesday evening into early Thursday. Another
  chance for rain this weekend.

- Temperatures rebound to a few degrees above normal Tuesday,
  then well above normal temperatures into the weekend with some
  records possible on Wednesday.

&&

.DISCUSSION...
Issued at 1155 PM CDT Mon Oct 26 2026

Precip and Storm Chances...Rain showers and sprinkles will
continue overnight into early Tuesday, mainly along and north of
Hwy 29, as a shortwave, weak low pressure and push of WAA move
across MN and western WI. Highest PoPs (90%) will be over northern
WI, tapering off as you move south. Models have backed off on the
sub-freezing layer aloft, along with surface temps expected to
stay above freezing (and a warm ground), so just a cold rain is
expected across far northern WI tonight into early Tuesday. Mainly
dry conditions are expected on Tuesday, but a few light showers
or sprinkles will remain possible within the moist, WAA regime.
Another shortwave and frontal boundary will cross the region late
Wednesday into Thursday morning, bringing a round of showers
(70-100% chance). A ribbon of mainly elevated instability will
move into the area late Wednesday (likely after sunset), bringing
low thunder chances (15-30%, highest south). No severe weather is
expected. Rainfall totals from Tuesday morning through Thursday
morning look to remain on the light side for most/all of the area,
with probabilities of over 0.25" near 50% from Wood to Vilas
County, but probabilities for over 0.50" under 25%. But any rain
will help with the ongoing drought across northern WI. High
pressure settles over the Great Lakes on Thursday, with additional
shower chances arriving this weekend.

Temperatures...after a brief return to more seasonal temps on
Monday, a return to above normal temps starts on Tuesday with
highs rebounding back into the mid 50s to mid 60s. On Wednesday,
strong southerly flow in the warm sector will allow temps to climb
into the upper 60s to mid 70s, away from the shore of Lake
Michigan. This will be in record territory for at few sites (Green
Bay, Marshfield and Wausau) with a few other sites nearing their
records. Temps drop a little on Thursday with highs mainly in the
60s, then the above normal temps continue through the weekend,
with highs in the in the mid 50s to mid 60s.

&&

.AVIATION...for 12Z TAF Issuance
Issued at 558 AM CDT Tue Oct 27 2026

Low pressure over the central Plains along with the associated
warm front extending east from the low will lift northeast and
across the region over the next 24-36 hours. In the process,
widely scattered, light rain showers will continue over north-
central and far northeast WI through around 15Z Tue. Coverage
seems sufficiently sparse to exclude from the RHI TAFs.

Ceilings have deteriorated overnight with widespread IFR
conditions north of AUW and scattered MVFR ceilings were south.
These MVFR and IFR ceilings will be slow to rise this morning, and
confidence is low how quickly ceilings will improve. Tentatively
show the low ceilings scattering at 16Z, but there are some
indications that IFR ceilings could continue into the afternoon
(RHI especially). After some improvement, deterioration of
ceilings to IFR is likely to return to RHI/AUW/CWA after 05Z Wed.

Besides the showers, gusty southeast winds are expected to develop
after 15Z Tue and up to 20 kts over central to east-central WI.
As surface winds diminish late this afternoon, low level winds
shear is expected to develop at RHI after 21Z Tue.

&&

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

&&

$$

DISCUSSION.....Bersch
AVIATION.......MPC