NWS-Milwaukee/Sullivan Forecast Discussion

						FXUS63 KMKX 031011
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
411 AM CST Sat Jan 3 2026

.KEY MESSAGES...

- There is around a 60 percent chance for light snow for east
  central Wisconsin this morning, with a dusting to a half inch
  accumulation.

- Light snow will be the dominant precip type for much of
  southern Wisconsin late Sunday afternoon and evening, but
  there is a chance for freezing drizzle at times, all the way
  through mid Monday morning. At least some minor snow
  accumulation and hazardous travel are possible.

- Polar air to remain over southern Wisconsin through the
  weekend, then relatively mild temperatures move in for next
  week.

&&

.SHORT TERM...
Issued 409 AM CST Sat Jan 3 2026

Today through Sunday Night:

The mosaic of radars over MN and WI shows light returns over
most of the area early this morning, but individual radars have
a "donut" around them. The cloud base heights are 6000 ft or
higher and surface dewpoints are in the single digits. This all
points to dry air in the low levels. The weak mid level shortwave
trough tracking across the region is expected to produce a brief
period of sufficient lift for the snow in the mid levels to
overcome most of the dry air in the low levels during the
morning hours today. We are looking at a high pop/low precip
event for central and east central WI, meaning snow will be
falling out of the sky, but accumulations will be light. Areas
south of I-94 may not see any snow today. Snow chances will
exit eastern WI just after noon today.

Clear skies are expected tonight, although upstream satellite
and subtle low level warm air advection suggest that clouds
could linger. Clear skies would allow temps to get into the
single digits tonight, but if clouds hang on then lows will be
in the teens, similar to last night.

Look for increasing clouds Sunday as broad lift works its way
into the area as a mid level shortwave trough approaches from
the Northern Plains. By Sunday afternoon, the nose of the low
level jet, mid level vorticity advection, and left exit region
of the upper jet will all be in place over central WI. The area
of associated precip is expected to track across central and
portions of southern WI quickly during the afternoon and
evening. Looking at forecast soundings, the majority of the
precip will be just ahead of the warm front, meaning the column
of air would all be below freezing. However, a robust warm nose
along the front could push the air aloft above freezing and give
us a brief wintry mix of sleet or freezing rain. Areas toward
central WI have the best chance of all snow through the evening
(during the main period of forcing), while areas south could see
a mix of snow and freezing drizzle.

Snowfall amounts up to 1 inch are possible toward Sheboygan,
with a dusting south of there. The forecast snow ratios have
come down a bit (8:1 now) in east central WI and continue to be
lower elsewhere. Surface temperatures are expected to remain
below freezing during this whole event, so if we lose ice
crystals, then icing on untreated surfaces is a concern for the
evening commute for the end of a long holiday weekend.

The shortwave will exit after midnight, but the low level
(strong) warm air advection will continue into late Monday
morning. This would dry out the mid levels but not the low
levels and allow for a period of freezing drizzle. By late
Monday morning, temps should be above freezing and end any icing
potential. More details are included in the next section.

Cronce

&&

.LONG TERM...
Issued 409 AM CST Sat Jan 3 2026

Monday through Friday:

Weak ridging aloft and largely dry air within the column will keep
the region largely dry later Monday. However, there is some lift
and moisture from the WAA at 850mb late Sunday night into early
Monday morning. This is primarily a concern for central and east
central WI with some freezing drizzle Monday morning possible. In
addition, the moist low levels, very cool surface and rapid
warming with height may very well bring some freezing fog concerns
Monday morning as well. These risks will exit later Monday
morning moisture dissipates and we warm up a bit but the morning
commute, especially toward central WI may be a bit of a concern.

Weather will then be quiet through most of Monday night with
drier air in the column. Freezing fog will again be possible
Tuesday morning given the cool surface temperatures, rapid warming
aloft and moisture. As we head through Tuesday morning a surface
low and associated shortwave aloft will bring some rain chances.
Models are still a bit all over the place with the track of this
system but it stands to reason that some precip is possible
Tuesday morning and into the early afternoon. At onset, any
precip would likely be freezing rain as warm air aloft will melt
any ice and rapid temps falls near the surface will allow for rain
to freeze on contact. This look likely to be temporary as
temperatures at the surface will increase through the morning with
any precip becoming rain by the late morning and early afternoon.
This system will push fully out of the region Tuesday night.

Wednesday into Thursday according to models looks largely dry
behind the Tuesday system and the late week system. This is in
large part due to drier air aloft and lack of any real forcing.

However, our attention then turns to the late week system which
has the potential to be fairly impactful. The issue is there is a
ton of uncertainty among models with vast differences in intensity
of the system, the track, the timing (both when and how long)
and even the impact of temperatures on this system. In any case,
models both suggest that the while the onset may be rain the
back portion of this system will likely feature some level of
accumulating snow. How much, depends on factors mentioned above.
But the high end snow accumulation scenario lines up with the
ECMWF operational 0z run which shows a very wrapped up upper low
moving right over southern WI to which the surface low occludes
and slows down and high end snow can fall on the north side of
the low which would likely include banding from Fgen.

Kuroski

&&

.AVIATION...
Issued 409 AM CST Sat Jan 3 2026

The mosaic of radars over MN and WI shows light returns over
most of the area early this morning, but individual radars have
a "donut" around them. The cloud base heights are 6000 ft or
higher and surface dewpoints are in the single digits. This all
points to dry air in the low levels. The weak mid level shortwave
trough tracking across the region is expected to produce a brief
period of sufficient lift for the snow in the mid levels to
overcome most of the dry air in the low levels during the
morning hours today. We are looking at a high pop/low precip
event for central and east central WI, meaning snow will be
falling out of the sky, but accumulations will be light. Areas
south of I-94 may not see any snow today. Snow chances will
exit eastern WI just after noon.

Ceilings will be in the 6000 to 10000 ft range for the morning,
but could fall to around 4000 ft AGL this afternoon. The clouds
are expected to clear by this evening, but there is a chance
that they will stick around as low-end VFR through the night.

Cronce

&&

.MARINE...
Issued 409 AM CST Sat Jan 3 2026

Modest west northwest winds will prevail through Saturday night
as low pressure continues to weaken over Hudson Bay. A ridge of
high pressure will also extend from Minnesota into the Ohio
Valley during this time. The high will then move across Lake
Michigan on Sunday. Breezy southerly winds will then develop
Sunday night and linger into Monday morning, as a wave of low
pressure moves across the Upper Great Lakes.

Cronce

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...None.
LM...None.
&&

$$

Visit us at weather.gov/milwaukee

Follow us on Facebook, X, and YouTube at:
www.facebook.com/NWSMilwaukee
www.x.com/NWSMilwaukee
www.youtube.com/NWSMilwaukee