675
FZUS63 KMKX 190753
GLFLM

OPEN LAKE FORECAST for Lake Michigan
National Weather Service Milwaukee/Sullivan WI
253 AM CDT Wed Aug 19 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...

A cold front continues to slowly work its way southward down Lake
Michigan through this morning. Behind this front expect light
north-northwesterly winds eventually become more variable as high
pressure around 30.0 inches tracks through the western Great
Lakes today through Thursday. Then as the high pressure exits,
southwesterly winds and thunderstorm chances return later Friday
as another system drags another cold front across the Upper Great
Lakes region.

LMZ261-362-364-366-563-565-567-868-191515-
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-
253 AM CDT Wed Aug 19 2026

SHEBOYGAN WI TO PENTWATER MI NORTH...

.TODAY...Northwest winds 5 to 10 kt increasing to 10 to 15 kt
late this morning, then becoming west early this afternoon
becoming southwest 10 to 20 kt late. Waves 1 to 2 ft.
.TONIGHT...South winds 10 to 15 kt diminishing to 5 to 10 kt.
Waves 1 to 2 ft.
.THURSDAY...Southwest winds 5 to 10 kt becoming south 10 to
20 kt. Waves 1 ft or less building to 1 to 3 ft.
.THURSDAY NIGHT...South winds 10 to 20 kt. Waves 2 to 4 ft.
.FRIDAY...Southwest winds 15 to 25 kt increasing to 30 kt.
Showers likely in the morning, then chance of showers in the
afternoon. Waves 3 to 5 ft.
.FRIDAY NIGHT...Southwest winds 15 to 25 kt veering to northwest
10 to 20 kt. Chance of showers. Waves 3 to 5 ft subsiding to 2 to
4 ft.
.SATURDAY...Northwest winds 15 to 25 kt becoming north to 30 kt.
Waves 1 to 3 ft.
.SUNDAY...Northwest winds to 30 kt becoming north gales to 35 kt.
Waves 3 to 5 ft.

$$

LMZ080-669-671-673-675-777-779-870-872-874-876-878-191515-
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-
253 AM CDT Wed Aug 19 2026

SHEBOYGAN WI TO PENTWATER MI SOUTH...

.TODAY...North winds 5 to 10 kt increasing to 10 to 15 kt. Waves
1 to 3 ft subsiding to 1 to 2 ft.
.TONIGHT...Northeast winds 10 to 15 kt becoming east 5 to 10 kt.
Waves 1 to 2 ft.
.THURSDAY...Southeast winds 5 to 10 kt becoming south late in the
morning, then becoming south 10 to 15 kt early in the afternoon
increasing to 10 to 20 kt late. Waves 1 ft or less building to
1 to 3 ft.
.THURSDAY NIGHT...South winds 10 to 20 kt. Waves 1 to 3 ft.
.FRIDAY...Southwest winds 10 to 20 kt becoming south to 30 kt in
the afternoon. Chance of showers. Waves 3 to 5 ft.
.FRIDAY NIGHT...Southwest winds 15 to 25 kt becoming west 10 to
20 kt. Chance of showers. Waves 3 to 5 ft.
.SATURDAY...Northwest winds 15 to 25 kt becoming north to 30 kt.
Waves 2 to 4 ft.
.SUNDAY...North winds 15 to 25 kt increasing to 30 kt. Waves 4 to
6 ft occasionally to 8 ft.

$$

LMZ761-191515-
MAFOR 1910/
MICHIGAN NORTH 11800 12710 11610 11410 12300 11400. Waves 2 feet
or less.

MICHIGAN SOUTH 11810 12800 11810 11110 11100 12200. Waves 1 to 3
feet today. Waves 2 feet or less tonight.

$$


Wagner

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

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