New Berlin, Wisconsin 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

330
FXUS63 KMKX 150854
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
354 AM CDT Wed Oct 15 2025

.KEY MESSAGES...

- Scattered light showers will diminish through mid morning,
  with clouds lingering through much of the day.

- Light rain or sprinkles are possible Thursday night into Fri
  morning. Higher chances (60 to 80 %) of showers and a few
  thunderstorms are forecast along a cold front Friday night
  through Saturday. The forecast progression of this front is
  trending slower.

- One more warm and breezy day is expected Friday with highs in
  the 70s.

&&

.SHORT TERM...
Issued 354 AM CDT Wed Oct 15 2025

Today through Thursday:

The majority of this ongoing shower activity will depart from
west to east through 8 AM as the upper level shortwave exits
WI. However, expect a narrow band of light rain to linger along
the surface front through midday. We can see this forming
already along the front that is currently positioned from
Rochester to La Crosse. This front is expected to remain
stationary through mid day and should stay just south of a
Wisconsin Dells to Madison to Janesville line. It should
actually drift southwestward through the day and remain outside
of south central WI tonight.

The steady northeasterly winds will diminish by late morning, as
the pressure gradient eases especially in east central WI with
high pressure building in. Low clouds will persist over
southwest WI through at least the middle of the day, but we
should see them diminish near the lakeshore as low level dry air
returns.

Tonight, temperatures will drop into the lower to mid 40s across
central WI. If we clear out, then fog is likely. Right now, the
NAMNest is the only model showing a potential for fog near Fond
du Lac, Sheboygan, and West Bend.

The low level jet will kick up over MN and western WI tonight,
with the nose (and warm air advection) pushing into north
central WI Thu morning. A weak shortwave trough is expected to
ride the upper ridge across northern WI during the day Thu.
Therefore, northern WI has the higher chance (50-70%) for light
rain showers. Here in southern WI, a few models, particularly
the ECWMF, favor a swath of light rain to roll across the area
with weak and elevated warm air advection. Most models keep us
dry, and the HREF grand ensemble suggests less than a 10 percent
chance for precip between Wisconsin Dells and Sheboygan, with
zero chance to the south.

Cronce

&&

.LONG TERM...
Issued 354 AM CDT Wed Oct 15 2025

Thursday night through Tuesday:

The 500 mb ridge axis should gradually shift east of the area
Thursday night into Friday. High pressure at the surface should
also slide further east of the region during this time, with
increasing south winds developing within a tightening pressure
gradient. The steady warm air advection at 850 mb may bring enough
upward vertical motion and moisture for a few showers or
sprinkles Thursday night, generally north of I-94. Mainly dry
conditions are expected Friday. Temperatures should continue to
warm well above seasonal normal values for Friday, with highs
into at least the middle 70s over most of the area.

The main cold front should push east into the area later Friday
night or early Saturday morning, and exit southern WI from west
to east by early Saturday afternoon or early Saturday evening.
There remains differences in the timing of the frontal passage,
with the ECMWF/EPS on the slower side and the GEFS/GFS on the
quicker side. However, the 00z GFS came in with a slower
solution, closer to the EC now.

A band of showers and some thunderstorms should move through the
area sometime during this period, from strong low level
frontogenesis response and the focused warm air advection moving
over the region. There is some right entrance region divergence
aloft as well. The later the progression of the front, the better
the chances for some thundestorms to occur with peak heating
Saturday. The deep layer bulk shear is strong and may not take
much instability to get some stronger storms with gusty winds to
occur. Still uncertainty with this potential, so keep up with the
forecast.

The precipitation should end fairly quickly behind the front, as
strong cold air advection on northwest winds pushes into the area
by Saturday night.

A rather deep 500 mb trough should then shift through the region
Saturday night into Sunday. Some lingering moisture may result in
scattered showers at times during this period. Temperatures
should cool down to near or a little above seasonal normal values
Saturday night into Sunday. Trends beyond this point are very
uncertain, so will leave NBM PoPs and temperatures unchanged in
the forecast.

Wood

&&

.AVIATION...
Issued 354 AM CDT Wed Oct 15 2025

The majority of this ongoing shower activity will depart from
west to east through 8 AM as the upper level shortwave exits
WI. However, expect a narrow band of light rain to linger along
the surface front through midday.

We have a wide range of ceiling heights across southern WI
early this morning, generally ranging from around 5000 ft
toward Sheboygan to 600 ft toward Monroe and Platteville. There
is a surface front that will remain stationary through midday
across southwest WI, roughly from La Crosse to Middleton to
Janesville. IFR ceilings are most likely along and southwest of
this front. That front will slowly shift southwestward by late
afternoon, exiting southwest WI.

If we clear out toward east central WI tonight, then fog is
likely. Right now, the NAMNest is the only model showing a
potential for fog near Fond du Lac, Sheboygan, and West Bend.

Cronce

&&

.MARINE...
Issued 354 AM CDT Wed Oct 15 2025

High pressure of will cross Lake Superior today and tonight
while weakening. The breezy east-northeast winds will diminish
by late morning and become southeast by Thursday morning. Look
for the southeast winds to become breezy again Thursday night
into Friday morning as low pressure develops in North Dakota
and lifts into Manitoba.

The low will further deepen as it reaches the northern
Manitoba-Ontario border Friday afternoon. Gusty southerly winds
are expected over Lake Michigan as an associated surface trough
cold front approaches from Minnesota. Southerly gale force gusts
will be possible Friday afternoon and evening over the north
half of the lake.

A surface low is expected to deepen as it crosses Lake Michigan
Saturday night. Gusty northerly winds are expected Sunday with
gales possible again, this time over southern Lake Michigan.

The Small Craft Advisory continues for the nearshore areas of
southern WI due to gusty northeast winds and high waves. Winds
and waves will diminish from north to south through mid to late
morning. No change to the end time of the Advisory.

Cronce

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...None.
LM...Small Craft Advisory...LMZ643-LMZ644-LMZ645-LMZ646 until 10
AM Wednesday.

&&

$$

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