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Union, IL 7-Day Night Weather Forecast
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Union, IL Weather Forecast
Union, IL Weather Forecast Date: 1236 PM CDT Sat Sep 05 2026
The area/counties/county of: Mchenry, including the cities of: Crystal Lake, Algonquin, Mchenry, and Woodstock.or toggle through each period.
This Afternoon... Mostly cloudy early in the afternoon, then becoming partly cloudy. Highs in the lower 80s. Northeast winds around 10 mph.
Tonight... Partly cloudy. Lows in the lower 60s. Northeast winds 5 to 10 mph.
Sunday... Partly cloudy. Highs in the upper 70s. East winds 5 to 10 mph.
Sunday Night... Mostly clear. Lows in the upper 50s. East winds around 5 mph.
Labor Day... Mostly sunny in the morning, then becoming partly cloudy. Highs around 80. Southeast winds 5 to 10 mph.
Monday Night... Partly cloudy in the evening, then becoming mostly cloudy. Lows in the lower 60s.
Tuesday... Mostly cloudy. Highs in the mid 80s.
Tuesday Night... Partly cloudy in the evening, then mostly cloudy with a chance of showers with a slight chance of thunderstorms after midnight. Lows in the lower 70s. Chance of precipitation 40%.
Wednesday... Mostly cloudy in the morning, then becoming partly cloudy. Highs in the mid 80s.
Wednesday Night... Partly cloudy. Lows in the lower 60s.
Thursday... Partly cloudy. Highs in the upper 70s.
Thursday Night... Partly cloudy. Lows in the upper 50s.
POP = Probability of Precipitation
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