Chicago Nearshore Marine Forecasts by Zone

 
 

 
 
 
 
 
FORECAST For Wilmette Harbor to Northerly Island (LMZ741)
 
 
 
 
 LMZ740>742-310315-
 Winthrop Harbor to Wilmette Harbor IL-
 Wilmette Harbor to Northerly Island IL-
 Northerly Island to Calumet Harbor IL-
 245 PM CDT Mon Mar 30 2026
 
 SMALL CRAFT ADVISORY IN EFFECT FROM TUESDAY MORNING THROUGH
 WEDNESDAY EVENING
 

 TONIGHT
 South winds 10 to 20 kt becoming southwest 15 to 25
 kt. Chance of showers and thunderstorms in the late evening and
 overnight. Waves 1 to 3 ft building to 2 to 4 ft.

 TUESDAY
 Southwest winds 20 to 25 kt increasing to 30 kt.
 Chance of showers and thunderstorms in the morning, then showers
 with thunderstorms likely in the afternoon. Waves 2 to 4 ft.

 TUESDAY NIGHT
 North winds 20 to 25 kt. Rain showers with
 thunderstorms likely in the evening, then chance of showers
 overnight. Waves 3 to 5 ft building to 4 to 7 ft occasionally to
 9 ft.

 WEDNESDAY
 Northeast winds 20 to 25 kt. Chance of showers.
 Waves 5 to 8 ft occasionally to 10 ft.
 
 $$