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: 224 PM CST Thu Jan 22 2026




Tonight: West gales to 35 kt becoming northwest, then diminishing to 30 kt late. Intermittent flurries. Waves 3 to 5 ft building to 4 to 6 ft occasionally to 8 ft.

Friday: Northwest winds to 30 kt diminishing to 15 to 25 kt. Partly cloudy. Waves 4 to 6 ft occasionally to 8 ft subsiding to 3 to 5 ft.

Friday Night: Northwest winds 10 to 20 kt. Slight chance of snow showers overnight. Waves 2 to 4 ft.

Saturday: Northwest winds around 10 kt becoming east in the afternoon. Chance of snow. Waves 1 to 3 ft.

wave heights are for ice free areas.







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

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