


Great Lakes Forecast
Issued by NWS
Issued by NWS
548 FZUS63 KMKX 040143 GLFLM OPEN LAKE FORECAST for Lake Michigan National Weather Service Milwaukee/Sullivan WI 843 PM CDT Thu Jul 3 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... High pressure around 30.0 inches over the Ohio River Valley will move to the east tonight into Friday. Light north to northeast winds today will become east to southeast tonight. Winds will then shift south on Friday, as a warm front moves north through the region. South to southwest winds will then increase Friday night into Saturday night, as low pressure around 29.3 inches moves across northern Ontario into Hudson Bay. The low will pull a cold front through the region Saturday night into Sunday. Northwest winds will become north behind this front Sunday and linger Sunday night. Mainly small chances for thunderstorms are forecast later tonight into early Friday morning across southern portions of the lake. More widespread chances for showers and thunderstorms are forecast for later Saturday into Sunday, as the cold front crosses the lake. LMZ261-362-364-366-563-565-567-868-040915- 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- 843 PM CDT Thu Jul 3 2025 SHEBOYGAN WI TO PENTWATER MI NORTH... .REST OF TONIGHT...East winds 5 to 10 kt becoming southeast. Waves 1 to 2 ft. .FRIDAY...Southeast winds 10 to 15 kt becoming south 10 to 20 kt. Slight chance of showers and thunderstorms in the afternoon. Waves 1 to 3 ft. .FRIDAY NIGHT...South winds 10 to 20 kt becoming southwest. Waves 2 to 4 ft. .SATURDAY...Southwest winds 15 to 25 kt becoming south to 30 kt. Waves 2 to 4 ft building to 4 to 6 ft occasionally to 8 ft. .SATURDAY NIGHT...Southwest winds to 30 kt diminishing to 10 to 20 kt overnight. Showers likely with a chance of thunderstorms. Waves 4 to 6 ft occasionally to 8 ft. .SUNDAY...West winds 10 to 20 kt becoming north. Chance of showers. Waves 2 to 4 ft. .SUNDAY NIGHT...North winds 10 to 20 kt. Waves 1 to 3 ft. .MONDAY...North winds 10 to 15 kt increasing to 10 to 20 kt. Waves 1 to 3 ft. .TUESDAY...East winds 5 to 10 kt becoming south 10 to 15 kt. Waves 1 ft or less. $$ LMZ080-669-671-673-675-777-779-870-872-874-876-878-040915- 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- 843 PM CDT Thu Jul 3 2025 SHEBOYGAN WI TO PENTWATER MI SOUTH... .REST OF TONIGHT...Northeast winds 5 to 10 kt veering to southeast. Chance of showers and thunderstorms overnight. Waves 1 to 2 ft. .FRIDAY...South winds 10 to 15 kt increasing to 10 to 20 kt. Chance of showers and slight chance of thunderstorms in the morning, then slight chance of showers and thunderstorms in the afternoon. Waves 1 to 3 ft. .FRIDAY NIGHT...South winds 10 to 20 kt becoming southwest 10 to 15 kt. Waves 1 to 3 ft. .SATURDAY...South winds 10 to 20 kt increasing to 15 to 25 kt. Waves 2 to 4 ft building to 4 to 6 ft occasionally to 8 ft. .SATURDAY NIGHT...South winds 15 to 25 kt becoming southwest 10 to 20 kt. Chance of showers and thunderstorms overnight. Waves 4 to 6 ft occasionally to 8 ft. .SUNDAY...Southwest winds 10 to 20 kt veering to northwest. Chance of showers in the morning, then chance of showers and thunderstorms in the afternoon. Waves 3 to 5 ft. .SUNDAY NIGHT...North winds 10 to 20 kt. Waves 1 to 3 ft. .MONDAY...North winds 10 to 15 kt increasing to 10 to 20 kt. Waves 1 to 3 ft. .TUESDAY...Northeast winds 5 to 10 kt becoming east 10 to 15 kt. Waves 1 to 2 ft. $$ LMZ761-040915- MAFOR 0404/ MICHIGAN NORTH 11300 12310 12410 13420. Waves 1 foot or less overnight. Waves 1 to 3 feet Friday and Friday evening. MICHIGAN SOUTH 11200 11310 15410. A chance of showers and thunderstorms overnight. A chance of showers Friday morning. Waves 2 feet or less. $$ Boxell Experimental modernized open lake forecast is available online at weather.gov/mkx/glftable Graphical marine forecasts are available online at: weather.gov/greatlakes