827
FZUS63 KMKX 300749
GLFLM

OPEN LAKE FORECAST for Lake Michigan
National Weather Service Milwaukee/Sullivan WI
249 AM CDT Sat Aug 30 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...

30.1 inch high pressure is centered over central Lake Michigan
this morning, resulting in light east-northeast winds across the
southern third of the open waters and light/variable winds further
north. The high will linger over the Lower Peninsula of Michigan
through the beginning of next week, resulting in broadly
persistent light/variable winds through Monday afternoon. Similar
to ongoing conditions, periods of more sustained east-northeast
winds may develop over the southern third of the waters both
tonight and Sunday night. Sustained south to southwest winds will
become established Tuesday afternoon, and will steadily increase
Tuesday night as 29.8 inch low pressure migrates from Ontario
toward Lake Superior. The low will progress toward the Ontario-
Quebec border on Wednesday, dragging a cold front across the open
waters in the process. The frontal passage will result in a
northwest wind shift, with winds becoming gusty Wednesday
afternoon and evening. While the current forecast continues to
keep gusts just below gale thresholds, upward trends are possible
as this portion of the period draws closer. Breezy northwest winds
will continue through the day on Thursday behind the departed
cold front. Periods of showers and thunderstorms will accompany
the passing cold front Wednesday morning through Wednesday night.
It remains too early to definitively indicate if gusty
thunderstorm winds or waterspouts will be possible in any of this
activity, though forecast trends will be closely monitored
through the beginning of next week.

LMZ261-362-364-366-563-565-567-868-301515-
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-
249 AM CDT Sat Aug 30 2025

SHEBOYGAN WI TO PENTWATER MI NORTH...

.TODAY...West winds less than 10 kt becoming southwest 10 to
15 kt. Waves 1 ft or less.
.TONIGHT...Southwest winds 5 to 10 kt becoming west. Waves 1 ft
or less.
.SUNDAY...Southwest winds less than 10 kt increasing to 10 to
15 kt. Waves nearly calm.
.SUNDAY NIGHT...South winds 5 to 10 kt diminishing to less than
10 kt. Waves nearly calm.
.MONDAY...South winds 5 to 10 kt becoming southwest. Waves nearly
calm.
.MONDAY NIGHT...South winds 5 to 10 kt. Waves nearly calm.
.TUESDAY...Southwest winds 10 to 15 kt increasing to 10 to 20 kt.
Waves 1 to 2 ft.
.WEDNESDAY...West winds 15 to 25 kt becoming north to 30 kt.
Showers likely with a chance of thunderstorms. Waves 2 to 4 ft
building to 3 to 5 ft.

$$

LMZ080-669-671-673-675-777-779-870-872-874-876-878-301515-
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-
249 AM CDT Sat Aug 30 2025

SHEBOYGAN WI TO PENTWATER MI SOUTH...

.TODAY...East winds 5 to 10 kt becoming north. Waves 1 ft or
less.
.TONIGHT...North 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.
.SUNDAY NIGHT...Northeast winds 5 to 10 kt becoming east. Waves
1 ft or less.
.MONDAY...East winds 5 to 10 kt becoming northeast. Waves 1 ft or
less.
.MONDAY NIGHT...Northeast winds 5 to 10 kt becoming east. Waves
1 ft or less.
.TUESDAY...Southeast winds 5 to 10 kt becoming south. Waves 1 ft
or less.
.WEDNESDAY...West winds 10 to 20 kt becoming northwest 15 to
25 kt. Showers likely with a chance of thunderstorms. Waves 3 to
5 ft building to 4 to 6 ft occasionally to 8 ft.

$$

LMZ761-301515-
MAFOR 3010/
MICHIGAN NORTH 12600 13510 12500 11600. Waves 1 foot or less.

MICHIGAN SOUTH 13200 11100 12800 11100 11200. Waves 1 foot or
less.

$$


Quigley

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

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