Coastal Waters Forecast for Winthrop Harbor to Wilmette Harbor IL (LMZ740) (Text-Only)
NWS Forecast for: Winthrop Harbor to Wilmette Harbor IL (LMZ740)
Issued by: National Weather Service Chicago, IL
Last Update: 918 PM CST Mon Feb 9 2026




Rest Of Tonight: South winds 15 to 25 kt becoming southwest 10 to 20 kt overnight. Mostly cloudy. Waves 2 to 4 ft.

Tuesday: Northwest winds 20 to 25 kt. Mostly cloudy in the morning, then becoming partly cloudy. Waves 1 to 3 ft.

Tuesday Night: Northwest winds 15 to 20 kt. Partly cloudy in the evening, then becoming mostly cloudy. Waves 2 to 4 ft.

Wednesday: Northwest winds 15 to 20 kt diminishing to 10 to 15 kt. Mostly cloudy in the morning, then becoming partly cloudy. Waves 2 to 4 ft.

wave heights are for ice free areas.







Zone Forecast: Winthrop Harbor to Wilmette Harbor IL (LMZ740)

Visit your local NWS office at: https://www.weather.gov/lot