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City of DeKalb, IllinoisDeKalb, IL 7-Day Night Weather Forecast
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DeKalb, IL Weather Forecast
DeKalb, IL Weather Forecast Date: 936 AM CDT Fri Sep 04 2026
The area/counties/county of: De Kalb, including the cities of: Dekalb and Sycamore.or toggle through each period.
Rest of Today... Mostly sunny. Highs in the lower 90s. Southwest winds 5 to 10 mph. Heat index values up to 104.
Tonight... Partly cloudy. A slight chance of showers and thunderstorms in the late evening and overnight. Humid with lows in the lower 70s. West winds around 5 mph. Chance of precipitation 20%.
Saturday... Mostly sunny. Humid with highs in the upper 80s. North winds 5 to 10 mph.
Saturday Night... Partly cloudy. Humid with lows in the mid 60s. Northeast winds 5 to 10 mph.
Sunday... Partly cloudy. Highs in the lower 80s. East winds 5 to 10 mph.
Sunday Night... Partly cloudy. Lows in the lower 60s.
Labor Day... Partly cloudy. Highs in the lower 80s.
Monday Night... Partly cloudy. Lows in the lower 60s.
Tuesday... Mostly cloudy. Highs in the mid 80s.
Tuesday Night... Partly cloudy. A chance of showers after midnight. Lows in the lower 70s. Chance of precipitation 40%.
Wednesday... Mostly cloudy. Highs in the upper 80s.
Wednesday Night... Partly cloudy. A chance of showers after midnight. Lows in the upper 60s. Chance of precipitation 40%.
POP = Probability of Precipitation
DeKalb Radar Loop
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