| NWS Forecast for: Northerly Island to Calumet Harbor IL (LMZ742) Issued by: National Weather Service Chicago, IL Last Update: 400 AM CDT Mon Aug 17 2026 |  |
| Today: Northwest winds 10 to 15 kt becoming northeast 15 to 20 kt early this morning, then becoming east around 10 kt mid afternoon. Slight chance of showers. Waves 2 to 4 ft subsiding to 1 to 3 ft. Tonight: Southeast winds 10 to 15 kt becoming southwest overnight. Mostly clear. Waves 1 to 2 ft. Tuesday: Southwest winds 10 to 15 kt. Chance of showers and thunderstorms in the afternoon. Waves 1 to 2 ft. Tuesday Night: West winds 10 to 15 kt becoming northwest overnight. Showers likely and a chance of thunderstorms. Waves 1 to 2 ft. | |
| Zone Forecast: Northerly Island to Calumet Harbor IL (LMZ742) | |
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