FZUS63 KMKX 211358 GLFLM OPEN LAKE FORECAST for Lake Michigan National Weather Service Milwaukee/Sullivan WI 858 AM CDT Mon Sep 21 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... High pressure around 30.4 inches north of Lake Superior today will shift eastward into Quebec tonight. The high will then largely remain in place through the middle of the week, while strengthening to around 30.7 inches by Wednesday morning. Gusty east to northeast winds are expected today through Wednesday. Winds then look to diminish toward the end of the week, as the high pressure system slowly weakens and moves farther east. LMZ261-362-364-366-563-565-567-868-212115- 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- 858 AM CDT Mon Sep 21 2026 SHEBOYGAN WI TO PENTWATER MI NORTH... .REST OF TODAY...East winds 15 to 25 kt becoming northeast. Waves 4 to 7 ft occasionally to 9 ft subsiding to 3 to 5 ft. .TONIGHT...Northeast winds 15 to 25 kt becoming east 10 to 20 kt. Waves 4 to 6 ft occasionally to 8 ft. .TUESDAY...East winds 10 to 20 kt becoming northeast 15 to 25 kt. Waves 3 to 5 ft. .TUESDAY NIGHT...East winds 15 to 25 kt diminishing to 10 to 20 kt. Waves 4 to 6 ft occasionally to 8 ft. .WEDNESDAY...East winds 10 to 20 kt becoming northeast 15 to 25 kt. Waves 2 to 4 ft. .WEDNESDAY NIGHT...East winds 15 to 25 kt becoming southeast 10 to 20 kt. Waves 2 to 4 ft. .THURSDAY...East winds 10 to 15 kt increasing to 10 to 20 kt. Waves 1 to 3 ft. .FRIDAY...Southeast winds 5 to 10 kt becoming east 10 to 15 kt. Waves 1 to 2 ft. $$ LMZ080-669-671-673-675-777-779-870-872-874-876-878-212115- Lake Michigan from Michigan City IN to St. Joseph MI 5 NM offshore to Mid Lake- Lake Michigan from Sheboygan to Port Washington WI 5 NM offshore to Mid Lake- Lake Michigan from Port Washington to North Point Light WI 5 NM offshore to Mid Lake- Lake Michigan from North Point Light to Wind Point WI 5 NM offshore to Mid Lake- Lake Michigan from Wind Point WI to Winthrop Harbor IL 5 NM offshore to Mid Lake- Lake Michigan from Winthrop Harbor to Wilmette Harbor IL 5 NM offshore to Mid Lake- Lake Michigan from Wilmette Harbor IL to Michigan City IN 5 NM offshore to Mid Lake- Lake Michigan from Whitehall to Pentwater MI 5 NM offshore to Mid Lake- Lake Michigan from Grand Haven to Whitehall MI 5 NM offshore to Mid Lake- Lake Michigan from Holland to Grand Haven MI 5 NM offshore to Mid Lake- Lake Michigan from South Haven to Holland MI 5 NM offshore to Mid Lake- Lake Michigan from St. Joseph to South Haven MI 5 NM offshore to Mid Lake- 858 AM CDT Mon Sep 21 2026 SHEBOYGAN WI TO PENTWATER MI SOUTH... .REST OF TODAY...East winds to 30 kt becoming northeast 15 to 25 kt. Waves 7 to 10 ft occasionally to 13 ft. .TONIGHT...Northeast winds 15 to 25 kt becoming east. Waves 5 to 8 ft occasionally to 10 ft. .TUESDAY...East winds 15 to 25 kt becoming northeast. Waves 4 to 7 ft occasionally to 9 ft. .TUESDAY NIGHT...East winds 15 to 25 kt. Waves 5 to 8 ft occasionally to 10 ft. .WEDNESDAY...East winds 15 to 25 kt becoming northeast. Waves 4 to 7 ft occasionally to 9 ft. .WEDNESDAY NIGHT...East winds 10 to 20 kt. Waves 3 to 5 ft. .THURSDAY...East winds 10 to 20 kt becoming northeast 10 to 15 kt. Waves 3 to 5 ft. .FRIDAY...East winds 10 to 15 kt becoming northeast. Waves 1 to 3 ft. $$ LMZ761-212115- MAFOR 2116/ MICHIGAN NORTH 13130 12230 13220. Waves 3 to 6 feet. MICHIGAN SOUTH 11140 12130 14230 11130. Waves 5 to 9 feet subsiding to 4 to 7 feet this afternoon. Waves 4 to 7 feet tonight. Waves 3 to 6 feet building to 4 to 7 feet Tuesday morning. $$ DDV Experimental modernized open lake forecast is available online at weather.gov/mkx/glftable Graphical marine forecasts are available online at: weather.gov/greatlakes