129
FZUS63 KMKX 090852
GLFLM

OPEN LAKE FORECAST for Lake Michigan
National Weather Service Milwaukee/Sullivan WI
352 AM CDT Sun Aug 9 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...

Southerly winds will persist this morning as a low pressure
trough around 29.8 inches approaches from the Minnesota Arrowhead.
An unsettled weather pattern will set up over the Upper Great
Lakes all week where weak waves of low pressure will cross the
region and produce rounds of thunderstorms at times. The first
round of weakening storms should arrive in southern Lake Michigan
late Sunday morning, and additional storms are possible there
Sunday night.

Winds today will be southerly and breezy, then grow light and
variable for a time tonight ahead of a cold front. The front will
move southward down the lake into Monday, leading to light
northerly winds through the morning on Monday and light and
variable winds Monday afternoon and evening. Light and variable
winds then persist into Tuesday as high pressure of 30.0 inches
remains in place north of a frontal boundary parked over the Corn
Belt.

LMZ261-362-364-366-563-565-567-868-091515-
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-
352 AM CDT Sun Aug 9 2026

SHEBOYGAN WI TO PENTWATER MI NORTH...

.TODAY...Southwest winds 10 to 20 kt becoming south. Slight
chance of showers this morning, then chance of showers this
afternoon. Waves 2 to 4 ft.
.TONIGHT...Southwest winds 10 to 20 kt diminishing to 10 to 15 kt
late in the evening, then diminishing to 5 to 10 kt after
midnight becoming northwest late. Slight chance of showers and
thunderstorms in the evening. Patchy fog overnight. Waves 2 to
4 ft subsiding to 1 to 3 ft.
.MONDAY...North winds 5 to 10 kt backing to south 10 to 15 kt.
Waves 1 to 2 ft.
.MONDAY NIGHT...Southeast winds 10 to 15 kt becoming northeast.
Waves 1 ft or less.
.TUESDAY...East winds 5 to 10 kt becoming northeast 10 to 15 kt.
Chance of showers. Waves 1 ft or less.
.TUESDAY NIGHT...North winds 5 to 10 kt. Waves 1 ft or less.
.WEDNESDAY...Northwest winds 5 to 10 kt becoming north 10 to
20 kt. Waves 1 ft or less.
.THURSDAY...North winds 10 to 20 kt increasing to 15 to 25 kt.
Waves 1 to 3 ft.

$$

LMZ080-669-671-673-675-777-779-870-872-874-876-878-091515-
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-
352 AM CDT Sun Aug 9 2026

SHEBOYGAN WI TO PENTWATER MI SOUTH...

.TODAY...South winds 10 to 20 kt. Chance of showers and
thunderstorms this afternoon. Waves 2 to 4 ft.
.TONIGHT...South winds 10 to 20 kt becoming west. Chance of
showers and thunderstorms in the evening, then chance of showers
and slight chance of thunderstorms overnight. Patchy fog
overnight. Waves 2 to 4 ft.
.MONDAY...Northwest winds 10 to 15 kt veering to northeast 5 to
10 kt. Waves 1 to 3 ft subsiding to 1 to 2 ft.
.MONDAY NIGHT...Northeast winds 5 to 10 kt. Showers likely with a
chance of thunderstorms in the evening, then showers likely
overnight. Waves 1 ft or less.
.TUESDAY...East winds 5 to 10 kt becoming northeast 10 to 15 kt.
Chance of showers. Waves 1 ft or less.
.TUESDAY NIGHT...Northeast winds 5 to 10 kt. Chance of showers
and thunderstorms. Waves 1 ft or less.
.WEDNESDAY...North winds 5 to 10 kt becoming northwest 10 to
15 kt. Waves 1 ft or less.
.THURSDAY...North winds 10 to 20 kt increasing to 15 to 25 kt.
Waves 1 to 3 ft.

$$

LMZ761-091515-
MAFOR 0910/
MICHIGAN NORTH 12520 12430 11420 11510 11500 11600. A chance of
showers this afternoon. Waves 1 to 3 feet building to 2 to 4 feet
today. Waves 1 to 3 feet tonight.

MICHIGAN SOUTH 11410 12420 11426 12420 11426 11520. A chance of
thunderstorms this afternoon and tonight. Waves 1 to 3 feet.

$$


CMiller

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

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