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: 947 AM CDT Tue Aug 11 2026




Rest Of Today: Southeast winds 10 to 15 kt. Showers and thunderstorms. Some thunderstorms may be severe late in the morning. Waves 1 to 2 ft.

Tonight: Southeast winds around 10 kt becoming around 5 kt. Partly cloudy in the evening, then becoming mostly cloudy. Waves around 1 ft.

Wednesday: South winds around 5 kt becoming southeast in the afternoon. Slight chance of showers and thunderstorms in the morning, then chance of showers and thunderstorms in the afternoon. Waves 1 ft or less.

Wednesday Night: Northeast winds around 10 kt becoming around 5 kt. Slight chance of showers and thunderstorms. Waves around 1 ft.







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

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