NWS-Milwaukee/Sullivan Forecast Discussion

						FXUS63 KMKX 290401
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
1101 PM CDT Fri Aug 28 2026

.KEY MESSAGES...

- Showers are likely at times Saturday into Saturday night with
  slight chances for thunderstorms.

- Becoming very warm and humid Sunday and persisting much of
  the new week. Scattered showers and thunderstorms, some strong
  at times, for the new week.

- A Small Craft Advisory may be needed late Saturday night into
  Sunday morning, particularly north of North Point Lighthouse.
  A Beach Hazard Statement may also be needed for Sheboygan and
  Ozaukee Counties.

&&

.SHORT TERM...
Issued 1101 PM CDT Fri Aug 28 2026

Today through Saturday:

Skies have momentarily cleared over srn WI but cirrus clouds
upstream will move swd into srn WI during the overnight. Lgt
sly winds will prevail at times through the night as the
pressure gradient increases slightly due to a wave of low
pressure moving ewd across the nrn Great Plains. Do not expect
any organized areas of fog to form.

For Saturday the shortwave trough currently over ND will round
the ewd moving upper ridge and move across WI from late Sat AM
through the afternoon. A well organized 700 mb baroclinic zone
will accompany this feature with forecast soundings showing
sufficient moisture and saturation for showers. PWATs will
increase to 1.5-1.7 inches during the afternoon, but mid level
lapse rates will remain poor, inhibiting most storm development.
Rain chances of 60-80 percent are forecast along and north of a
line from Dodgeville to Madison to Mequon but still 40-50
percent chances to the south.

The shortwave trough will move away Sat evening but a swly 850
mb jet around 35-40 kts will veer slightly from central WI into
srn WI through the night. The warm, moist advection will
persist and support rain chances of 40-60 percent over ern WI
with lesser chances over south central WI. Elevated CAPE will
begin to gradually climb through the night as steeper mid level
lapse rates arrive. The low level jet and associated thetae
advection will still support sct showers and storms Sun AM, but
mid level capping will then reduce or completely inhibit showers
and storms for a time Sun afternoon and evening.

The clouds and intermittent showers will keep temps down a bit
on Sat, but the arrival of a warm front late Sat nt and Sun will
boost high temps into the middle 80s with dewpoints approaching
70F for Sun afternoon.


Gehring

&&

.LONG TERM...
Issued 1101 PM CDT Fri Aug 28 2026

Sunday night through Friday:

A broad but low amplitude upper ridge will prevail over the
central and srn USA through mid week with srn WI on the nrn
periphery of the flat ridge. A swly low level jet will reside in
the area from Sun nt-Tue nt, but the persistent moisture
transport and weak warm advection will be offset by warm mid
level temperatures. Thus shower and storms chances will range
from 20-40 percent at times, but a more organized area of
showers and storms may develop late Tue nt with the passage of a
weak Canadian cold front. Cannot rule out some strong or severe
storms as MUCAPE will rise to 2000 J/KG Mon-Tue with mdt deep
layer shear in place. Very warm and humid conditions are
expected through Wed then lessening for Thu-Fri as the upper
ridge retrogrades toward the Great Plains and sfc ridging builds
south from Canada.

Gehring

&&

.AVIATION...
Issued 1101 PM CDT Fri Aug 28 2026

VFR conditions tnt-Sat nt, but periods of showers are expected
Saturday into Saturday night along with isolated thunderstorms.
Cigs of 5-8 kft can be expected at times with local Cigs of
3.5-5.0 kft. LLWS may develop late Sat evening through the night
if a swly low level jet increases to 40-45 kts.

Gehring

&&

.MARINE...
Issued 1101 PM CDT Fri Aug 28 2026

High pressure around 30.1 inches will gradually move east of the
lower Great Lakes on Saturday, while low pressure deepens to
around 29.6 inches in the central Great Plains. This will support
modest to breezy southerly winds from Saturday afternoon through
Monday as the low will remain well to the west. Scattered
thunderstorms will occur at times from Saturday night into next
week. A weak cold front will finally arrive late Tuesday night and
Wednesday with light northerly winds eventually taking hold.

A Small Craft Advisory may be needed north of North Point
Lighthouse late Saturday night and Sunday if waves build to 3 to
5 feet.

Gehring

&&

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

$$

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