NWS-Green Bay Forecast Discussion

						FXUS63 KGRB 110753
AFDGRB

Area Forecast Discussion
National Weather Service Green Bay WI
253 AM CDT Wed Mar 11 2026

Forecast discussion for routine morning forecast issuance

.KEY MESSAGES...

- Hazardous travel expected this morning through the early
  afternoon from snow across the northwoods. Light mixed
  precipitation across much of central to east-central Wisconsin
  may also result in some slippery stretches.

- Medium to high (50-90%) chances for at least 4 inches of snow
  across northern into central Wisconsin Thursday night into
  Friday, along with strong, gusty winds.

- Widespread accumulating snow potential exists over the weekend
  (60-80% probability), which may impact weekend travel.

&&

.DISCUSSION...
Issued at 253 AM CDT Wed Mar 11 2026

Today...
A lull in the active weather is possible for the early
to mid morning period as forcing associated with the warm air
advection subsides. Still, some drizzle will fill at times as
soundings suggest plenty of saturation through the lowest levels,
which remains in line with recent surface observations. Freezing
drizzle does remain in the forecast for this period as result with
probability of a glaze still staying around 50-70%, but the
overall impacts may be limited as road temperature observations
suggest they have remained just above freezing. Still, will keep
headlines for the morning period as temperatures may still drop a
couple of degrees and elevated surfaces such as bridges, trees,
and possibly some sidewalks may still be vulnerable to icing. Snow
will return from west to east in the mid to late morning hours as
the upper trough rolls through the region which will bring some
additional snow to many areas. The highest impacts will be across
north-central Wisconsin, where an additional 1-3 inches seems
likely before snow departs in the afternoon. The second round may
again bring a very brief freezing precipitation threat in the mid
to late morning, but overall temperature profiles suggest a
changeover to predominantly snow.

Thursday Night into Friday...
Attention then turns to the next wintry system that lies in store
for the region. A strong mid-level trough and amplified surface
wave will bring another period of precipitation to the region
starting Thursday evening. This will be a fast moving system, with
precipitation exiting by Friday afternoon. The most intense
snowfall will likely be associated with the upper trough
overnight in the hours around midnight and could see snowfall
rates briefly approach an inch an hour for a couple hours.
Therefore confidence in snow totals of at least 6 inches is
growing, with probabilistic showing around 40-60% for areas north
of a line from Merrill and Marinette. Further south, a relatively
warm temperature profile suggests a wetter snow with a lower SLR
and also that rain will mid in at times once you get into portions
of central and east-central Wisconsin. Thus a sharp gradient
between the higher snow totals and relatively low ones seems
likely, which will also make this system sensitive to any
north/south shifts in the forecast. Winds will further complicate
the forecast with ensemble probabilities retaining around 50% to
70% chance of at least 35 mph wind gusts at times. All together,
winter weather impacts are becoming likely (50-80% via WSO),
especially across northern Wisconsin where the snow confidence is
higher.

Weekend System...
A third round of winter weather will be possible over the weekend
as another mid-level trough crosses the Upper Midwest over the
weekend. Long range guidance is in relatively good agreement that
this system will bring impactful winter weather to areas around
the Great Lakes, with higher snowfall driven by high PWATs, ample
upper forcing, and gusty winds. What is not in agreement remains
the details of the storm track (i.e. the who gets what) driven
mainly be disagreements in the amplitude of the wave and overall
storm track of the resulting low. Additional details will be
refined over the coming days as we get better sampling on the
upstream system, but do keep an eye on the forecast if you plan on
traveling in the region this weekend.

&&

.AVIATION...for 06Z TAF Issuance
Issued at 1112 PM CDT Tue Mar 10 2026

Flying conditions will continue to deteriorate late this evening,
dropping to MVFR/IFR. A band of snow will continue to impact areas
north of RHI. As the initial band of rain showers pushes north, a
period of lighter precip, including some drizzle and freezing
drizzle, along with a lulls in the precip for some, is expected
late this evening. The precip will fill back in and the rain and
wintry mix will slowly change over to snow from northwest to
southeast Wednesday morning. Highest snow accumulations will be
across north-central WI, with a glazing of ice expected across
much of central and eastern WI. Conditions will improve from west
to east Wednesday afternoon.

Northeast winds will remain gusty overnight, especially near the
Bay and Lake Michigan, where gust to around 30 kts will continue.
Winds will slowly shift to the north then northwest on Wednesday.

&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning until 1 PM CDT this afternoon for WIZ005-
010>012.

Winter Weather Advisory until 1 PM CDT this afternoon for WIZ013-
018>022-030-031-035>040-045-048>050-073-074.
&&

$$

DISCUSSION.....Uhlmann
AVIATION.......Bersch