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: 919 AM CDT Wed Mar 18 2026


Rest Of Today: South winds 15 to 25 kt diminishing to 10 to 15 kt this afternoon. Chance of snow showers late in the morning. Waves 3 to 5 ft subsiding to 2 to 4 ft.

Tonight: Southwest winds around 10 kt. Scattered showers overnight. Waves 1 to 2 ft.

Thursday: South winds around 5 kt becoming northeast in the afternoon. Scattered showers in the morning. Waves 1 to 2 ft.

Thursday Night: Northeast winds around 10 kt becoming south overnight. Mostly cloudy. Waves 1 to 2 ft.







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

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