854
FZUS63 KMKX 311934
GLFLM

OPEN LAKE FORECAST for Lake Michigan
National Weather Service Milwaukee/Sullivan WI
234 PM CDT Sun Aug 31 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...

High pressure around 30.3 inches will linger over the region into
Tuesday, which will continue to bring light winds over Lake
Michigan. Southwest winds will become established Tuesday night,
as low pressure around 29.6 inches develops near Lake Superior.

The low will slowly move to the Ontario and Quebec border
Wednesday and Wednesday night, dragging a strong cold front across
Lake Michigan. The frontal passage will result in a gusty
northwest wind shift across the waters Wednesday night, with gusty
winds lingering into Thursday.

The current forecast winds remain below gale force thresholds
during this period for the open waters, though increases to or
above gale force may occur in later forecasts.

Showers and thunderstorms will accompany the passing cold front
Wednesday into Wednesday night. It remains too early to pinpoint
any possibility for waterspouts with this activity and any showers
the rest of the week, though forecast trends will be closely
monitored. Breezy west winds will continue through Friday.

LMZ261-362-364-366-563-565-567-868-010315-
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-
234 PM CDT Sun Aug 31 2025

SHEBOYGAN WI TO PENTWATER MI NORTH...

.TONIGHT...Southwest winds 5 to 10 kt becoming south. Waves 1 ft
or less.
.MONDAY...Southwest winds less than 10 kt becoming west. Waves
nearly calm.
.MONDAY NIGHT...Southeast winds 5 to 10 kt becoming southwest.
Waves nearly calm.
.TUESDAY...Southwest winds 5 to 10 kt increasing to 10 to 15 kt.
Waves 1 ft or less.
.TUESDAY NIGHT...South winds 10 to 15 kt becoming southwest 10 to
20 kt. Waves 1 to 3 ft.
.WEDNESDAY...Southwest winds 10 to 20 kt increasing to 15 to
25 kt. Chance of showers in the morning, then showers with a
chance of thunderstorms in the afternoon. Waves 2 to 4 ft
building to 3 to 5 ft.
.WEDNESDAY NIGHT...West winds 15 to 25 kt becoming northwest.
Chance of showers. Waves 3 to 5 ft.
.THURSDAY...West winds 15 to 25 kt increasing to 30 kt. Waves
3 to 5 ft.
.FRIDAY...Southwest winds 15 to 25 kt becoming west. Chance of
showers. Waves 4 to 6 ft occasionally to 8 ft.

$$

LMZ080-669-671-673-675-777-779-870-872-874-876-878-010315-
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-
234 PM CDT Sun Aug 31 2025

SHEBOYGAN WI TO PENTWATER MI SOUTH...

.TONIGHT...Northeast winds 10 to 15 kt becoming east. Waves 1 to
2 ft.
.MONDAY...Southeast winds less than 10 kt increasing to 5 to
10 kt late in the morning, then becoming east early in the
afternoon becoming north 10 to 15 kt late. Waves 1 to 2 ft.
.MONDAY NIGHT...North winds 10 to 15 kt veering to east. Waves
1 to 2 ft.
.TUESDAY...Southeast winds 5 to 10 kt becoming south. Waves 1 ft
or less.
.TUESDAY NIGHT...South winds 5 to 10 kt increasing to 10 to
15 kt. Waves 1 to 2 ft.
.WEDNESDAY...Southwest winds 10 to 20 kt increasing to 15 to
25 kt. Chance of showers in the afternoon. Waves 2 to 4 ft
building to 3 to 5 ft.
.WEDNESDAY NIGHT...West winds 15 to 25 kt becoming northwest.
Chance of showers. Waves 4 to 6 ft occasionally to 8 ft building
to 4 to 7 ft occasionally to 9 ft.
.THURSDAY...Northwest winds 15 to 25 kt becoming west to 30 kt.
Waves 4 to 7 ft occasionally to 9 ft.
.FRIDAY...Southwest winds 15 to 25 kt becoming west to 30 kt.
Chance of showers. Waves 4 to 7 ft occasionally to 9 ft.

$$

LMZ761-010315-
MAFOR 3122/
MICHIGAN NORTH 11500 13400 11500 12400 11500. Waves 1 foot or
less.

MICHIGAN SOUTH 11110 12100 12200 11300 11200 11810. Waves 1 foot
or less.

$$
Wood

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

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