191
FZUS63 KMKX 240202
GLFLM

OPEN LAKE FORECAST for Lake Michigan
National Weather Service Milwaukee/Sullivan WI
902 PM CDT Sun Aug 23 2026

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...

Low pressure around 29.7 inches in eastern Ontario linger through
Monday, resulting in breezy northwest wind across the northern
third of the Lake. Gusts are expected to approach gales at times.
High pressure around 30.1 inches high pressure will build into
the Upper Mississippi Valley, reaching the waters by Monday
afternoon. Winds will diminish across the Lake as the high moves
overhead becoming light and variable. The high will shift east
into Ontario by Tuesday, resulting in a south-southwest wind shift
across the waters. 29.7 inch low pressure will approach from the
northern Great Plains Tuesday night into Wednesday, reinforcing
the south-southwesterly wind pattern. The low will cross Lake
Michigan during the second half of the day Wednesday, bringing a
breezy northwest wind shift. Gales are not expected as this
occurs. Showers and thunderstorms will accompany the
approaching/passing surface low Tuesday night into Wednesday
afternoon. It remains too early to tell if any of these storms
could be severe, with trends being monitored through the beginning
of this week. The next area of 30.1 inch high pressure will
gradually build toward Lake Michigan from the northern Great
Plains Wednesday night through Friday, bringing slowly decreasing
winds.

LMZ261-362-364-366-563-565-567-868-240930-
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-
902 PM CDT Sun Aug 23 2026

SHEBOYGAN WI TO PENTWATER MI NORTH...

.REST OF TONIGHT...North winds to 30 kt becoming northwest. Waves
4 to 6 ft occasionally to 8 ft.
.MONDAY...Northwest winds to 30 kt becoming north 15 to 25 kt.
Waves 4 to 6 ft occasionally to 8 ft subsiding to 2 to 4 ft.
.MONDAY NIGHT...North winds 10 to 20 kt diminishing to 5 to
10 kt. Waves 1 to 3 ft subsiding to 1 to 2 ft.
.TUESDAY...Southwest winds 10 to 15 kt increasing to 15 to 25 kt
in the afternoon. Waves 1 to 2 ft building to 2 to 4 ft.
.TUESDAY NIGHT...South winds 15 to 25 kt. Chance of showers
overnight. Waves 3 to 5 ft.
.WEDNESDAY...South winds to 30 kt becoming southwest. Showers in
the morning, then showers likely with a chance of thunderstorms
in the afternoon. Waves 4 to 7 ft occasionally to 9 ft.
.WEDNESDAY NIGHT...West winds 15 to 25 kt becoming northwest
10 to 20 kt. Waves 4 to 6 ft occasionally to 8 ft subsiding to
2 to 4 ft.
.THURSDAY...Northwest winds 15 to 25 kt increasing to 30 kt.
Waves 2 to 4 ft.
.FRIDAY...North winds 10 to 20 kt. Waves 1 to 2 ft.

$$

LMZ080-669-671-673-675-777-779-870-872-874-876-878-240930-
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-
902 PM CDT Sun Aug 23 2026

SHEBOYGAN WI TO PENTWATER MI SOUTH...

.REST OF TONIGHT...North winds 10 to 20 kt becoming northwest.
Waves 3 to 5 ft.
.MONDAY...Northwest winds 10 to 20 kt becoming north. Waves 2 to
4 ft.
.MONDAY NIGHT...North winds 10 to 20 kt diminishing to 5 to 10 kt
late in the evening, then becoming west after midnight becoming
west 5 to 10 kt late. Waves 2 to 4 ft subsiding to 1 to 2 ft.
.TUESDAY...Southwest winds 10 to 15 kt becoming south 10 to
20 kt. Waves 1 to 2 ft building to 2 to 4 ft.
.TUESDAY NIGHT...South winds 10 to 20 kt increasing to 15 to
25 kt. Waves 3 to 5 ft.
.WEDNESDAY...Southwest winds to 30 kt. Chance of showers in the
morning, then chance of showers and thunderstorms in the
afternoon. Waves 4 to 7 ft occasionally to 9 ft.
.WEDNESDAY NIGHT...Southwest winds 15 to 25 kt becoming west
10 to 20 kt. Waves 4 to 6 ft occasionally to 8 ft subsiding to
2 to 4 ft.
.THURSDAY...Northwest winds 10 to 20 kt. Waves 2 to 4 ft.
.FRIDAY...North winds 10 to 15 kt becoming northeast 10 to 20 kt.
Waves 1 to 2 ft.

$$

LMZ761-240930-
MAFOR 2404/
MICHIGAN NORTH 12740 13730 12830 11810. Waves 3 to 6 feet
overnight. Waves 3 to 5 feet subsiding to 1 to 3 feet Monday.
Waves 1 to 3 feet Monday evening.

MICHIGAN SOUTH 11820 11710 13720 12820 11810. Waves 2 to 4 feet
overnight. Waves 1 to 3 feet building to 2 to 4 feet Monday.
Waves 1 to 3 feet Monday evening.

$$


Patterson

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

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