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Old Gillespie Lake, IL 7-Day Night Weather Forecast
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Old Gillespie Lake, IL Weather Forecast
Old Gillespie Lake, IL Weather Forecast Date: 608 AM CDT Tue Aug 11 2026
The area/counties/county of: Greene County Il, Jersey County Il.or toggle through each period.
Today... Mostly sunny. Highs in the mid 90s. Southwest winds 5 to 10 mph with gusts up to 20 mph. Heat index values up to 105.
Tonight... Partly cloudy with a chance of thunderstorms with a slight chance of showers in the evening, then mostly clear after midnight. Lows in the mid 70s. Southwest winds 5 to 10 mph. Chance of rain 30%. Heat index values up to 104 early in the evening.
Wednesday... Mostly sunny. A slight chance of showers and thunderstorms in the morning, then a chance of showers and thunderstorms in the afternoon. Humid with highs in the lower 90s. Southwest winds 5 to 10 mph. Chance of rain 50%. Heat index values up to 106.
Wednesday Night... Partly cloudy with a slight chance of showers and thunderstorms in the evening, then mostly cloudy with a chance of showers and thunderstorms after midnight. Humid with lows in the lower 70s. Southeast winds around 5 mph. Chance of rain 50%. Heat index values up to 105 early in the evening.
Thursday... Partly sunny with a chance of showers and thunderstorms. Humid with highs in the lower 90s. East winds around 5 mph. Chance of rain 50%. Heat index values up to 102.
Thursday Night... Mostly cloudy. Showers and thunderstorms likely. Lows around 70. Highs in the upper 80s. Chance of rain 70%. Heat index values up to 100.
Friday... Mostly cloudy. Showers and thunderstorms likely. Lows around 70. Highs in the upper 80s. Chance of rain 70%. Heat index values up to 100.
Friday Night... Partly cloudy. Lows in the lower 70s. Highs in the mid 90s. Heat index values up to 105.
Saturday... Partly cloudy. Lows in the lower 70s. Highs in the mid 90s. Heat index values up to 105.
Saturday Night... Mostly clear. Lows in the mid 70s. Heat index values up to 105 early in the evening.
Sunday... Mostly sunny. Highs in the lower 90s. Heat index values up to 105.
Sunday Night... Partly cloudy. A chance of showers and thunderstorms. Lows in the upper 60s. Highs in the mid 80s. Chance of rain 40%. Heat index values up to 100.
POP = Probability of Precipitation
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