| NWS Forecast for: Northerly Island to Calumet Harbor IL (LMZ742) Issued by: National Weather Service Chicago, IL Last Update: 408 AM CDT Tue May 19 2026 |  |
Today: Southwest winds 20 to 25 kt becoming west 15 to 25 kt late. Chance of showers and slight chance of thunderstorms in the morning, then chance of showers and thunderstorms in the afternoon. Waves 2 to 4 ft subsiding to 1 to 3 ft. Tonight: Northwest winds 15 to 20 kt becoming north. Partly cloudy. Waves 1 to 3 ft building to 2 to 4 ft. Wednesday: North winds 15 to 20 kt becoming northeast. Mostly cloudy in the morning, then becoming partly cloudy. Waves 3 to 5 ft. Wednesday Night: North winds 15 to 25 kt becoming northeast 15 to 20 kt. Partly cloudy. Waves 3 to 5 ft. | |
| Zone Forecast: Northerly Island to Calumet Harbor IL (LMZ742) | |
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