


Northerly Island to Calumet Harbor IL Marine Forecast
Updated 9:15pm CDT Aug 26, 2026
Rest Of Tonight
Northwest winds 10 to 15 kt. Mostly clear.
Thursday
Northwest winds around 10 kt becoming northeast in the afternoon. Mostly sunny. Waves 1 to 2 ft.
Thursday Night
Northeast winds around 10 kt becoming east.
Friday
East winds around 5 kt becoming southeast. Mostly sunny. Waves 1 to 2 ft.