NWS-Milwaukee/Sullivan Forecast Discussion

						FXUS63 KMKX 281107 AAA
AFDMKX

Area Forecast Discussion...UPDATED
National Weather Service Milwaukee/Sullivan WI
607 AM CDT Fri Aug 28 2026

.KEY MESSAGES...

- Patchy dense fog is possible through early this morning,
  particularly in low lying areas.

- Multiple periods of showers and storms forecast from this
  weekend into early next week, with a sharp transition to
  warmer and more humid conditions.

- Small Craft Advisory-criteria conditions may return to the
  nearshore waters on Sunday, particularly for zones north of
  Milwaukee. A Beach Hazard Statement may also be needed on
  Sunday.

&&

.UPDATE...
Issued 607 AM CDT Fri Aug 28 2026

Patchy fog will continue early this morning and could be briefly
dense in a few spots. Fog should dissipate fairly quickly post
sunrise as daytime mixing kicks in. Otherwise, quiet weather is
expected today under high pressure, with no significant updates
to the short term forecast anticipated through the afternoon
hours.

DDV

&&

.SHORT TERM...
Issued 1136 PM CDT Thu Aug 27 2026

Tonight through Friday night:

High pressure over wrn Ontario will move into the nrn Great
Lakes late tnt then shift to the lower Great Lakes on Fri. Good
radiational cooling conditions will lead to areas of fog over
low lying areas of south central WI late tnt. Partly cloudy
skies and another lake breeze is then expected on Fri with highs
in the lower 80s away from the lake. Lgt sly winds and the onset
of warm advection is expected Fri nt but any precipitation
should hold off until Sat.

Gehring

&&

.LONG TERM...
Issued 1136 PM CDT Thu Aug 27 2026

Saturday through Thursday:

A broad, but low amplitude upper ridge, will move into the
central and srn USA this weekend and continue into next week.
Well organized low to mid level warm, moist advection that will
bring the ridge into the central USA, will affect srn WI Sat
afternoon and night. PWATs will rise above 1.5 inches but mid
level lapse rates will remain poor through Sat nt with only very
limited CAPE developing. Showers are still likely with some
storms Sat afternoon and night when the main tropospheric
baroclinic zone moves across the region. The mid level lapse
rates will steepen on Sunday as the elevated mixed layer arrives
but the warming temps aloft will also contribute to capping.
MUCAPE should rise above 1000 J/KG for Sun-Mon and some warm,
moist advection will continue on a swly low level jet into Mon.
Rain chances of 20-50 percent are forecast.

A shortwave trough will then pass to the north Tue nt but drag a
weak cold front through srn WI. 40 percent chances for showers
and storms are forecast. Afterward an upper ridge will either
build through the Great Plains or back nwd into the central USA
and Upper MS River Valley. Overall a very warm and humid week
is expected beginning on Sunday.

Gehring

&&

.AVIATION...
Issued 607 AM CDT Fri Aug 28 2026

Patchy fog this morning could be briefly dense a few locations.
The fog should dissipate most places by around 13Z. Otherwise,
quiet weather is expected today under high pressure, with light
south to southwest winds away from the lake, becoming southeast
near the lake by the afternoon. Scattered diurnal cumulus
clouds with bases around 5 kft are also expected late morning
into the afternoon. Light southerly winds will continue tonight,
with increasing high clouds from the west ahead of an
approaching low pressure system.

DDV

&&

.MARINE...
Issued 1136 PM CDT Thu Aug 27 2026

High pressure of 30.1 inches will move from Ontario into the
northern Great Lakes by Friday morning then shift into the lower
Great Lakes by Friday evening. Light northeast to easterly flow is
expected tonight becoming light to modest southerly flow for
Friday afternoon and night. Modest to breezy southerly winds will
then prevail this weekend and on Monday as a trough of low
pressure slowly moves from the Great Plains to the Upper
Mississippi River Valley. Rounds of thunderstorms can be expected
over Lake Michigan from Saturday night into early next week.

A Small Craft Advisory may be needed on Sunday for persistent
south winds and building waves.

Gehring

&&

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

$$

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