Allouez, Wisconsin Weather Forecast Discussion

224
FXUS63 KGRB 290722
AFDGRB
Area Forecast Discussion
National Weather Service Green Bay WI
222 AM CDT Mon Sep 29 2025
Forecast discussion for routine morning forecast issuance
.KEY MESSAGES...
- Patchy dense fog and low clouds are expected across the region
  tonight. The fog will likely affect the morning commute on
  Tuesday.
- An extended period of dry and low-impact weather is forecast
  through the next week. Above to much above average temperatures
  are expected during this time frame.
&&
.DISCUSSION...
Issued at 221 AM CDT Mon Sep 29 2025
Some patchy fog has been noted this morning across the region;
however, with a dearth of moisture, as evidenced by the very dry
00Z KGRB RAOB sounding and the 0.53 inch PWAT value from the
sounding, the fog will not be widespread with a low impact across
the region.
Mostly sunny skies and warm 850 mb temperatures in the middle
teens will bring another very warm day to the region as highs soar
to around 80 degrees across the north with lower 80s across
central and east-central Wisconsin away from the lakeshore.
A weak cold front will drop south tonight, which will bring
slightly cooler temperatures to the region. Fog should be more
ubiquitous tonight as model soundings show low level moisture
trapped in the lowest levels of the atmosphere. Model and MOS
guidance also hint at a better chance for widespread fog tonight;
therefore, bumped up the intensity and coverage of the fog across
the region tonight. The fog will likely affect the morning commute
on Tuesday as sunrise is getting fairly late in the year.
Canadian high pressure will ridge across the Great Lakes region
through the rest of the week, and will be slow to shift east due
to the blocking influence of a couple tropical systems in the
western Atlantic. The frontal passage will bring a minor cooling
trend mid-week, followed by much above normal temperatures into
the early part of the weekend. Recent model trends are a bit
quicker with the frontal passage and chances for precipitation
this upcoming weekend, with a chance for showers across central
and north-central Wisconsin on Saturday and the rest of the region
Saturday night. The slow moving nature of the front will mean
small chances for rain will continue through the rest of the
weekend into early next week. This period of the forecast doesn`t
look to be a washout, with periods of dry periods interspersed at
times, but with exact timing hard to pinpoint at this juncture.
Winds will pick up a bit out of the southeast Wednesday night
into Thursday, leading to possible marine concerns (Small Craft
Advisories) on Lake Michigan, especially south of Two Rivers.
&&
.AVIATION...for 06Z TAF Issuance
Issued at 950 PM CDT Sun Sep 28 2025
No significant changes to the previous forecast. High confidence
in VFR conditions for all terminals (KGRB, KATW, KMTW, KAUW, KCWA,
KRHI) through the period. A dry airmass and high pressure will
result in clear skies and light winds.
The only potential for sub-VFR conditions is some patchy ground
fog toward sunrise Monday. The risk is very low for most sites,
but KRHI and perhaps KMTW have a slightly higher chance for a
brief period of IFR or MVFR visibility between 08Z and 12Z.
Otherwise, expect clear skies and calm winds overnight, becoming
E/NE at 5-10 KT on Monday afternoon.
OUTLOOK...
MVFR/IFR conditions possible late Monday night into Tuesday
morning due to fog/low stratus, but these conditions are after the
06Z TAF period.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
DISCUSSION.....Kurimski
AVIATION.......MPC

NWS GRB Office Area Forecast Discussion