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: 300 AM CDT Mon Jun 29 2026




Today: South winds 10 to 15 kt early, increasing to 20 to 25 kt by midday. Partly cloudy in the morning, then becoming mostly sunny. Waves 1 to 3 ft building to 2 to 4 ft.

Tonight: South winds 20 to 25 kt early in the evening, diminishing to 15 to 20 kt. Clear. Waves 2 to 4 ft subsiding to 1 to 3 ft.

Tuesday: Southwest winds 15 to 25 kt. Mostly sunny in the morning, then becoming partly cloudy. Waves 1 to 3 ft.

Tuesday Night: Southwest winds 15 to 25 kt. Clear. Waves 1 to 3 ft.







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

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