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Johnson County, IL 7-Day Night Weather Forecast
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Johnson County, IL Weather Forecast
Johnson County, IL Weather Forecast Date: 734 PM CST Mon Mar 02 2026
The area/counties/county of: Johnson, including the city of Vienna.or toggle through each period.
Tonight... Mostly cloudy. Patchy fog. A chance of showers with a slight chance of thunderstorms after midnight. Near steady temperature in the lower 40s. East winds around 5 mph. Chance of rain 50%.
Tuesday... Mostly cloudy with a chance of showers in the morning, then partly sunny with a slight chance of showers in the afternoon. Not as cool with highs in the upper 60s. South winds 5 to 10 mph. Chance of rain 40%.
Tuesday Night... Mostly cloudy. A chance of showers after midnight. Not as cool with lows in the mid 50s. South winds around 5 mph. Chance of rain 40%.
Wednesday... Mostly cloudy. Showers likely in the morning, then a chance of showers and thunderstorms in the afternoon. Highs in the mid 70s. South winds 5 to 10 mph. Chance of rain 60%.
Wednesday Night... Mostly cloudy with a chance of thunderstorms. A chance of showers in the evening, then showers likely after midnight. Lows around 60. South winds 5 to 10 mph. Chance of rain 70%.
Thursday... Showers in the morning, then showers likely with a chance of thunderstorms in the afternoon. Highs in the lower 70s. Chance of rain 80%.
Thursday Night... Mostly cloudy with a chance of showers. A chance of thunderstorms after midnight. Lows around 60. Chance of rain 50%.
Friday... Partly sunny. A chance of showers and thunderstorms in the morning. Highs in the upper 70s. Chance of rain 30%.
Friday Night... Partly cloudy in the evening, then mostly cloudy with a chance of showers after midnight. Lows in the lower 60s. Chance of rain 40%.
Saturday... Showers with a chance of thunderstorms in the morning, then showers likely in the afternoon. Highs in the lower 70s. Chance of rain 90%.
Saturday Night... Mostly cloudy with a 50% chance of showers. Lows in the lower 50s.
Sunday... Mostly cloudy with a 40% chance of showers. Highs in the upper 60s. Lows in the mid 50s.
Sunday Night... Mostly cloudy with a 40% chance of showers. Highs in the upper 60s. Lows in the mid 50s.
POP = Probability of Precipitation
Johnson County Radar Loop
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