311
FZUS63 KMKX 280752
GLFLM

OPEN LAKE FORECAST for Lake Michigan
National Weather Service Milwaukee/Sullivan WI
252 AM CDT Thu Aug 28 2025

FOR WATERS BEYOND FIVE NAUTICAL MILES OF SHORE ON Lake Michigan.

Waves are provided as a range of significant wave heights, which
is the average of the highest 1/3 of the wave, along with the
average height of the highest 10% of the waves which will
occasionally be encountered.

.SYNOPSIS...

A trough of low pressure and associated cold front are moving
south across the lake this morning. Southwest winds will continue
ahead of the cold front, veering due north to northeast behind
it. The passing front is producing scattered showers and isolated
thunderstorms, with some potential for waterspouts overnight over
the northern half of the lake, then over the southern half of the
lake today. The potential for waterspouts will linger over the
southern half through this afternoon behind the front.

This afternoon/evening north winds will become breezy. These winds
will subside tonight into Friday as high pressure around 30.2
inches builds in from the north. An extended period of light and
variable winds with quiet weather will then occur this weekend
through early next week, as high pressure around 30.2 inches
lingers over the upper Great Lakes.

LMZ261-362-364-366-563-565-567-868-281515-
Lake Michigan from Seul Choix Point to Rock Island Passage 5 NM
offshore to Mid Lake-
Lake Michigan South of a line from Seul Choix Point to the
Mackinac Bridge and north of a line from Charlevoix MI to South
Fox Island 5 NM offshore-
Lake Michigan from Charlevoix to Point Betsie MI 5 NM offshore to
Mid Lake-
Lake Michigan from Point Betsie to Manistee MI 5 NM offshore to
Mid Lake-
Lake Michigan from Rock Island Passage to Sturgeon Bay WI-
Lake Michigan from Sturgeon Bay to Two Rivers WI 5 NM offshore to
Mid Lake-
Lake Michigan from Two Rivers to Sheboygan WI 5 NM offshore to
Mid Lake-
Lake Michigan from Pentwater to Manistee MI 5 NM offshore to Mid
Lake-
252 AM CDT Thu Aug 28 2025

SHEBOYGAN WI TO PENTWATER MI NORTH...

.TODAY...North winds 10 to 20 kt increasing to 30 kt. Slight
chance of showers this morning. Waves 2 to 4 ft building to 4 to
7 ft occasionally to 9 ft.
.TONIGHT...North winds 15 to 25 kt becoming northeast 10 to
20 kt. Waves 4 to 7 ft occasionally to 9 ft subsiding to 3 to
5 ft.
.FRIDAY...Northeast winds 10 to 15 kt becoming north. Waves 2 to
4 ft subsiding to 1 to 2 ft.
.FRIDAY NIGHT...North winds 10 to 15 kt backing to southwest.
Waves 1 ft or less.
.SATURDAY...Southwest winds 10 to 15 kt. Waves 1 ft or less.
.SATURDAY NIGHT...Southwest winds 10 to 15 kt diminishing to 5 to
10 kt. Waves 1 ft or less.
.SUNDAY...Southwest winds 5 to 10 kt increasing to 10 to 15 kt.
Waves nearly calm.
.MONDAY...Southwest winds 5 to 10 kt increasing to 10 to 15 kt.
Waves nearly calm.

$$

LMZ080-669-671-673-675-777-779-870-872-874-876-878-281515-
Lake Michigan from Michigan City IN to St. Joseph MI 5 NM
offshore to Mid Lake-
Lake Michigan from Sheboygan to Port Washington WI 5 NM offshore
to Mid Lake-
Lake Michigan from Port Washington to North Point Light WI 5 NM
offshore to Mid Lake-
Lake Michigan from North Point Light to Wind Point WI 5 NM
offshore to Mid Lake-
Lake Michigan from Wind Point WI to Winthrop Harbor IL 5 NM
offshore to Mid Lake-
Lake Michigan from Winthrop Harbor to Wilmette Harbor IL 5 NM
offshore to Mid Lake-
Lake Michigan from Wilmette Harbor IL to Michigan City IN 5 NM
offshore to Mid Lake-
Lake Michigan from Whitehall to Pentwater MI 5 NM offshore to Mid
Lake-
Lake Michigan from Grand Haven to Whitehall MI 5 NM offshore to
Mid Lake-
Lake Michigan from Holland to Grand Haven MI 5 NM offshore to Mid
Lake-
Lake Michigan from South Haven to Holland MI 5 NM offshore to Mid
Lake-
Lake Michigan from St. Joseph to South Haven MI 5 NM offshore to
Mid Lake-
252 AM CDT Thu Aug 28 2025

SHEBOYGAN WI TO PENTWATER MI SOUTH...

.TODAY...West winds 10 to 20 kt becoming northwest late this
morning, then becoming north to 30 kt this afternoon. Chance of
waterspouts. Chance of showers and slight chance of thunderstorms
this morning, then slight chance of showers this afternoon. Waves
3 to 5 ft building to 5 to 8 ft occasionally to 10 ft.
.TONIGHT...North winds to 30 kt becoming northeast 10 to 20 kt.
Waves 5 to 8 ft occasionally to 10 ft subsiding to 4 to 7 ft
occasionally to 9 ft.
.FRIDAY...Northeast winds 10 to 15 kt becoming north. Waves 3 to
5 ft subsiding to 1 to 3 ft.
.FRIDAY NIGHT...Northeast winds 10 to 15 kt diminishing to 5 to
10 kt. Waves 1 to 2 ft.
.SATURDAY...East winds 5 to 10 kt becoming northeast. Waves 1 ft
or less.
.SATURDAY NIGHT...Northeast winds 5 to 10 kt becoming east. Waves
1 ft or less.
.SUNDAY...East winds 5 to 10 kt becoming northeast. Waves 1 ft or
less.
.MONDAY...East winds 5 to 10 kt becoming northeast. Waves 1 ft or
less.

$$

LMZ761-281515-
MAFOR 2810/
MICHIGAN NORTH 12820 14830 12120. A chance of showers early this
morning. Waves 2 to 4 feet building to 4 to 7 feet today. Waves 4
to 7 feet subsiding to 2 to 4 feet tonight.

MICHIGAN SOUTH 11620 11720 11730 11830 11840 11830 11130 11120. A
chance of waterspouts today. A chance of showers this morning.
Waves 3 to 5 feet subsiding to 2 to 4 feet, then building to 4 to
7 feet today. Waves 5 to 8 feet subsiding to 3 to 6 feet tonight.

$$


Patterson

Experimental modernized open lake forecast is available online at
weather.gov/mkx/glftable

Graphical marine forecasts are available online at:
weather.gov/greatlakes