


Great Lakes Forecast
Issued by NWS
Issued by NWS
432 FZUS63 KMKX 300143 GLFLM OPEN LAKE FORECAST for Lake Michigan National Weather Service Milwaukee/Sullivan WI 843 PM CDT Tue Jul 29 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... Winds are variable across the southern half of the open waters, with northerly winds across approximately the northern half as a stationary front lingers near the midpoint of the lake. Late tonight into Wednesday, expect this front to push southward, bringing north-northeasterly gusts through the remainder of the open waters. Thunderstorms will develop across the southern half into Wednesday morning as weak low pressure around 29.9 inches over the Middle Mississippi Valley pushes eastward into the Ohio Valley. Widespread severe weather is not anticipated, though a few storms could produce gusty winds across the far southern portions of the lake. High pressure around 30.3 inches will then settle into the western Great Lakes into Thursday. Northeasterly winds will diminish into the weekend and become light and variable. LMZ261-362-364-366-563-565-567-868-300915- 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 Tue Jul 29 2025 SHEBOYGAN WI TO PENTWATER MI NORTH... .REST OF TONIGHT...Northwest winds 10 to 15 kt becoming north 10 to 20 kt. Areas of smoke. Waves 1 to 3 ft. .WEDNESDAY...Northeast winds 10 to 20 kt becoming north 15 to 25 kt. Areas of smoke. Slight chance of showers in the afternoon. Waves 2 to 4 ft. .WEDNESDAY NIGHT...Northeast winds 15 to 25 kt diminishing to 10 to 20 kt. Areas of smoke in the evening. Waves 3 to 5 ft. .THURSDAY...Northeast winds 10 to 20 kt increasing to 15 to 25 kt. Waves 3 to 5 ft. .THURSDAY NIGHT...Northeast winds 15 to 25 kt diminishing to 10 to 20 kt. Waves 3 to 5 ft subsiding to 2 to 4 ft. .FRIDAY...North winds 10 to 15 kt increasing to 10 to 20 kt. Waves 1 to 3 ft. .FRIDAY NIGHT...Northwest winds 10 to 20 kt backing to south 5 to 10 kt. Waves 1 to 3 ft. .SATURDAY...Southwest winds 10 to 15 kt increasing to 10 to 20 kt. Waves 1 to 2 ft. .SUNDAY...Southwest winds 10 to 15 kt increasing to 10 to 20 kt. Waves 1 to 2 ft. $$ LMZ080-669-671-673-675-777-779-870-872-874-876-878-300915- 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 Tue Jul 29 2025 SHEBOYGAN WI TO PENTWATER MI SOUTH... .REST OF TONIGHT...North winds 5 to 10 kt becoming northeast 10 to 20 kt. Waves 1 ft or less building to 1 to 3 ft. .WEDNESDAY...Northeast winds 10 to 20 kt becoming north 15 to 25 kt. Slight chance of showers in the morning, then chance of showers and thunderstorms in the afternoon. Waves 2 to 4 ft building to 3 to 5 ft. .WEDNESDAY NIGHT...Northeast winds to 30 kt diminishing to 15 to 25 kt. Showers likely with a chance of thunderstorms in the evening, then chance of showers overnight. Waves 5 to 8 ft occasionally to 10 ft. .THURSDAY...Northeast winds 10 to 20 kt becoming north 15 to 25 kt. Waves 4 to 7 ft occasionally to 9 ft. .THURSDAY NIGHT...Northeast winds 15 to 25 kt diminishing to 10 to 20 kt. Waves 4 to 7 ft occasionally to 9 ft. .FRIDAY...Northeast winds 10 to 20 kt becoming north. Waves 3 to 5 ft. .FRIDAY NIGHT...North winds 10 to 20 kt becoming east 5 to 10 kt. Waves 2 to 4 ft. .SATURDAY...Southeast winds 5 to 10 kt becoming northeast 10 to 15 kt. Waves 1 to 3 ft. .SUNDAY...South winds 5 to 10 kt increasing to 10 to 15 kt. Waves 1 ft or less. $$ LMZ761-300915- MAFOR 3004/ MICHIGAN NORTH 12820 11120 11810 11820 12830 11130. Waves 1 to 3 feet overnight. Waves 1 to 3 feet building to 2 to 4 feet Wednesday. Waves 2 to 4 feet Wednesday evening. MICHIGAN SOUTH 11820 12120 11110 11120 11830 11136 11146. A chance of thunderstorms Wednesday afternoon and Wednesday evening. Waves 1 to 3 feet overnight. Waves 1 to 3 feet building to 3 to 5 feet Wednesday. Waves 3 to 6 feet building to 4 to 7 feet Wednesday evening. $$ MH Experimental modernized open lake forecast is available online at weather.gov/mkx/glftable Graphical marine forecasts are available online at: weather.gov/greatlakes