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: 946 AM CST Sun Nov 30 2025




Rest Of Today: Northwest winds to 30 kt diminishing to 20 to 25 kt late in the afternoon. Chance of snow late in the morning, then a chance of flurries in the afternoon. Waves 4 to 6 ft occasionally to 8 ft.

Tonight: Northwest winds 15 to 25 kt diminishing to 10 to 15 kt. Partly cloudy. Waves 4 to 6 ft occasionally to 8 ft subsiding to 3 to 5 ft.

Monday: West winds around 10 kt becoming southwest in the afternoon. Snow in the afternoon. Waves 1 to 3 ft.

Monday Night: Southwest winds 10 to 15 kt becoming west overnight. Snow in the evening, then chance of snow overnight. Waves 1 to 2 ft.







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

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