NWS-Milwaukee/Sullivan Forecast Discussion

						FXUS63 KMKX 260017 AAA
AFDMKX

Area Forecast Discussion...UPDATED
National Weather Service Milwaukee/Sullivan WI
717 PM CDT Mon May 25 2026

.KEY MESSAGES...

- A Moderate Swim Risk remains into this evening for Lake
  Michigan beaches in Sheboygan and Ozaukee Counties.

- There are 20 to 50 percent chances for showers and some storms
  Tuesday evening and night, as a backdoor cold front starts to
  shift southward toward the area.

- A backdoor cold front Wednesday will bring gusty northeast
  winds behind it near the lake and much cooler temperatures.
  This front will also bring chances for showers and storms
  (around 20 to 50 percent) Wednesday afternoon/early evening.

- Dry for later this week into the weekend with above normal
  temperatures.

&&

.UPDATE...
Issued 717 PM CDT Mon May 25 2026

A moderate swim risk should linger into this evening for
Sheboygan and Ozaukee County beaches, due to lingering waves
around 3 feet. Winds will continue to weaken and will allow
waves to subside to 1 to 2 feet by later tonight.

High pressure to the southeast of the area will continue to push
east tonight into Tuesday. Some middle level clouds will
dissipate this evening, with mostly clear skies overnight into
Tuesday morning. Any lingering gusty south winds will weaken
this evening, with light south winds becoming southwest later
tonight into Tuesday morning. Lows tonight should be in the
upper 50s to around 60 degrees.

Another warm day is expected Tuesday, with highs into the upper
80s over most of the area. Winds should shift south to possibly
southeast closer to the lake in the afternoon, which may bring
cooler temperatures there.

Some middle level clouds may move through in the afternoon, with
some diurnal cumulus possible as well. Forecast soundings in
northwest parts of the area are showing building elevated CAPE,
but the area is capped to surface parcels, and any elevated
upward motion should remain to the north and northwest. Thus,
most CAMs suggest that any showers and storms remaining to the
north Tuesday afternoon, closer to the stationary front and
within the southwesterly low level jet axis.

This activity may sag southward into the area Tuesday evening
and night, as the front shifts southward as a cold front toward
the area. There is some differential CVA passing through
Tuesday night, with forecast soundings trying to show some
elevated CAPE up to 1000 J/kg in the afternoon and early in the
evening in northwest parts of the area, dropping quickly as the
night goes on. For now, kept 20 to 50 percent chances for
showers and storms going in the forecast over northern portions
of the area. Deep layer bulk shear is fairly weak, around 20
knots or less, so not expecting any strong to severe storms at
this time.

Wood

&&

.SHORT TERM...
Issued 1230 PM CDT Mon May 25 2026

Tonight through Wednesday night:

Tonight we will start to move into an upper level ridge setup
which will bring us very warm temperatures for Tuesday with
modest to breezy southwest flow on the backside of the surface
high. There will likely be some precip in the midwest region,
primarily focused along a warm front to the north, especially as
we move into Tuesday night as a developing high over the UP in
connection with a more pronounced high in central Canada will
turn the warm front into a southward moving backdoor cold front.

This backdoor cold front appears likely to be strong (pneumonia
front like in terms of impact?) rapidly pushing down the lake
into Wednesday. Models may not even be capturing how quickly
this may occur on Wednesday. While it should be expected to warm
up a bit ahead of this front if it comes through early enough
the warming may not be as substantial. In either case, we could
see quite a significant temperature drop behind the front. The
other piece of this is that depending on timing, this front
could trigger showers/storms during the day Wednesday. The issue
with precip chances is that the only forcing will be from the
front with no lift elsewhere given being in the base of the
ridge. The precip chances have increased for this period
however, given the strength of the front and enough low level
moisture to work with to bring about precip. Any storms with
this would be largely weak given the limited shear with the
ridge overhead but enough instability could allow for some
briefly strong storms likely quickly becoming outflow dominant.
Showers/storms may linger into the evening before the front
clears out as we lose instability into the evening.

A period of moderate swim risk conditions expected later this
afternoon through the evening primarily for Ozaukee and
Sheboygan counties with a risk for high swim risk conditions
Wednesday late afternoon through Wednesday night for all
nearshore counties.

Kuroski

&&

.LONG TERM...
Issued 1230 PM CDT Mon May 25 2026

Thursday through Monday:

Thursday and Friday remain in the same underlying pattern with
large scale ridging overhead and surface high pressure generally
overhead. Thursday has trended cooler due to the front coming
through Wednesday and Friday has trended toward producing
another backdoor cold front which is a bit uncertain still and
depends on progression of the surface high. This may introduce
some precip chances, though chances are uncertain at this time.
Into the weekend while the upper levels become potential more
active, though uncertain, the lack of moisture and the
likelihood of high pressure over the western Great Lakes
suggests it will likely remain dry through the weekend and
likely into early next week.

Kuroski

&&

.AVIATION...
Issued 717 PM CDT Mon May 25 2026

High pressure to the southeast of the area will continue to
push east tonight into Tuesday. Some middle level clouds will
dissipate this evening, with mostly clear skies overnight into
Tuesday morning.

Any lingering gusty south winds will weaken this evening, with
light south winds becoming southwest later tonight into Tuesday
morning. Winds should shift south to possibly southeast closer
to the lake in the afternoon. Some middle level clouds may move
through in the afternoon, with some diurnal cumulus possible as
well. Light and variable winds are expected Tuesday night.

Any showers and storms should remain to the north of the area
Tuesday afternoon, closer to the stationary front. This
activity may sag southward into the area Tuesday evening and
night, as the front shifts southward as a cold front toward the
area. The better chances would be north and west of Madison at
this time.

Wood

&&

.MARINE...
Issued 1230 PM CDT Mon May 25 2026

High pressure around 30.2 inches will continue to drift east to
the eastern Great Lakes today. Fog has largely dissipated
across the lake. Modest southerly winds will continue tonight
into Tuesday, while high pressure around 30.3 inches is expected
to build toward eastern Hudson Bay Tuesday into Wednesday. This
will eventually move a cold front southward over Lake Michigan
for Tuesday night and Wednesday. Winds will shift northeasterly
behind the front. Another potential cold front sliding down the
lake possible Friday.

Kuroski

&&

.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