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: 346 AM CDT Tue Aug 26 2025




Early This Morning: Northwest winds around 20 kt. Clear. Waves 2 to 4 ft.

Today: Northwest winds around 20 kt becoming north 10 to 15 kt this morning. Partly cloudy in the morning, then becoming mostly cloudy. Waves 2 to 4 ft subsiding to 1 to 3 ft.

Tonight: North winds 10 to 15 kt becoming west 5 to 10 kt late. Mostly clear. Waves 1 to 3 ft subsiding to around 1 ft.

Wednesday: West winds 5 to 10 kt increasing to 10 to 15 kt. Mostly sunny in the morning, then becoming partly cloudy. Waves around 1 ft.

Wednesday Night: Southwest winds 10 to 15 kt. Slight chance of showers overnight. Waves 1 to 2 ft.







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

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