Coastal Waters Forecast for Northerly Island to Calumet Harbor IL (LMZ742) (Text-Only)
NWS Forecast for: Northerly Island to Calumet Harbor IL (LMZ742)
Issued by: National Weather Service Chicago, IL
Last Update: 200 AM CDT Wed Jul 29 2026




Early This Morning: North winds 10 to 20 kt. Mostly clear. waves 3 to 6 ft occasionally to 8 ft.

Today: North winds 10 to 15 kt becoming northeast this afternoon. Mostly sunny. Waves 2 to 4 ft subsiding to 1 to 3 ft.

Tonight: Northeast winds around 10 kt becoming light and variable. Mostly clear. Waves 1 to 2 ft subsiding to 1 ft or less.

Thursday: Light and variable winds becoming southeast around 10 kt in the afternoon. Partly cloudy. Waves around 1 ft.

Thursday Night: South winds around 10 kt. Mostly cloudy. Waves around 1 ft.







Zone Forecast: Northerly Island to Calumet Harbor IL (LMZ742)

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