


Great Lakes Forecast
Issued by NWS
Issued by NWS
842 FZUS63 KMKX 162204 GLFLM OPEN LAKE FORECAST for Lake Michigan National Weather Service Milwaukee/Sullivan WI 503 PM CDT Wed Jul 16 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... Low pressure of 29.7 inches over southern Wisconsin will track across southern Lake Michigan this evening while broad high pressure of 30.2 inches moves in from the Dakotas. This will lead to some strong northerly winds into Thursday. The high pressure will be tracking through the Great Lakes into Thursday night and Friday morning. A weak area of low pressure of 29.9 inches will track through the southwestern Lake Michigan area on Saturday as broad high pressure of 30.1 inches sets up acorss the upper Great Lakes. LMZ261-362-364-366-563-565-567-868-170900- 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- 503 PM CDT Wed Jul 16 2025 SHEBOYGAN WI TO PENTWATER MI NORTH... .TONIGHT...North winds to 30 kt. Showers likely with a chance of thunderstorms. Waves 4 to 6 ft occasionally to 8 ft building to 5 to 8 ft occasionally to 10 ft. .THURSDAY...North winds 15 to 25 kt increasing to 30 kt. Slight chance of showers in the morning. Waves 5 to 8 ft occasionally to 10 ft subsiding to 4 to 7 ft occasionally to 9 ft. .THURSDAY NIGHT...North winds 15 to 25 kt diminishing to 10 to 20 kt late in the evening, then becoming northeast 10 to 15 kt after midnight becoming east late. Waves 4 to 6 ft occasionally to 8 ft subsiding to 1 to 3 ft. .FRIDAY...South winds 5 to 10 kt becoming southwest. Waves 1 to 2 ft. .FRIDAY NIGHT...South winds 5 to 10 kt. Waves 1 ft or less. .SATURDAY...South winds 10 to 15 kt backing to northeast. Chance of showers. Waves 1 to 2 ft. .SATURDAY NIGHT...North winds 10 to 15 kt. Waves 1 to 2 ft. .SUNDAY...Northeast winds 10 to 15 kt becoming north. Waves 1 to 2 ft. .MONDAY...Southeast winds 10 to 20 kt becoming east. Waves 1 to 3 ft. $$ LMZ080-669-671-673-675-777-779-870-872-874-876-878-170900- 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- 503 PM CDT Wed Jul 16 2025 SHEBOYGAN WI TO PENTWATER MI SOUTH... .TONIGHT...South winds 15 to 25 kt veering to northwest to 30 kt. Showers likely with a chance of thunderstorms this evening, then chance of showers and slight chance of thunderstorms overnight. Waves 3 to 5 ft building to 5 to 8 ft occasionally to 10 ft. .THURSDAY...Northwest winds 15 to 25 kt becoming north to 30 kt. Slight chance of showers in the morning. Waves 5 to 8 ft occasionally to 10 ft. .THURSDAY NIGHT...North winds 15 to 25 kt diminishing to 10 to 20 kt late in the evening, then becoming northeast 10 to 15 kt after midnight becoming east late. Waves 4 to 7 ft occasionally to 9 ft subsiding to 2 to 4 ft. .FRIDAY...East winds 10 to 15 kt diminishing to 5 to 10 kt. Waves 2 to 4 ft subsiding to 1 to 2 ft. .FRIDAY NIGHT...East winds 5 to 10 kt veering to southeast. Waves 1 to 2 ft. .SATURDAY...South winds 10 to 15 kt becoming southwest. Chance of showers in the morning, then chance of showers and thunderstorms in the afternoon. Waves 1 to 2 ft. .SATURDAY NIGHT...North winds 10 to 15 kt. Chance of thunderstorms. Waves 1 to 2 ft. .SUNDAY...Northeast winds 10 to 15 kt becoming north. Waves 1 to 3 ft. .MONDAY...Southeast winds 10 to 20 kt. Chance of showers. Waves 2 to 4 ft. $$ LMZ761-170900- MAFOR 1707 AMD/ MICHIGAN NORTH 11846 11840 11830 12840 11830 11820. A chance of thunderstorms overnight. Waves 4 to 7 feet overnight. Waves 4 to 7 feet subsiding to 3 to 6 feet Thursday. Waves 3 to 5 feet subsiding to 2 to 4 feet Thursday evening. MICHIGAN SOUTH 12730 11830 12840 11830 11820. A chance of showers overnight. A slight chance of showers Thursday morning. Waves 4 to 7 feet overnight and Thursday. Waves 4 to 7 feet subsiding to 3 to 6 feet Thursday evening. $$ WFO MKX Experimental modernized open lake forecast is available online at weather.gov/mkx/glftable Graphical marine forecasts are available online at: weather.gov/greatlakes