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Little Flat Lake, IL 7-Day Night Weather Forecast
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Little Flat Lake, IL Weather Forecast
Little Flat Lake, IL Weather Forecast Date: 608 AM CDT Tue Aug 11 2026
The area/counties/county of: Clinton County Il, Washington County Il.or toggle through each period.
Today... Mostly sunny. Hot with highs in the mid 90s. Southwest winds 5 to 10 mph. Heat index values up to 109.
Tonight... Partly cloudy in the evening, then clearing. Humid with lows in the mid 70s. Southwest winds 5 to 10 mph. Heat index values up to 105 early in the evening.
Wednesday... Sunny. A slight chance of showers and thunderstorms in the afternoon. Hot with highs in the mid 90s. Southwest winds around 5 mph. Chance of rain 20%. Heat index values up to 113 in the afternoon.
Wednesday Night... Partly cloudy. A slight chance of showers and thunderstorms in the evening, then a chance of showers and thunderstorms after midnight. Humid with lows in the mid 70s. Southwest winds around 5 mph. Chance of rain 50%. Heat index values up to 108 early in the evening.
Thursday... Mostly sunny with a chance of showers and thunderstorms. Humid with highs in the mid 90s. Southwest winds around 5 mph, becoming southeast in the afternoon. Chance of rain 50%. Heat index values up to 109 in the afternoon.
Thursday Night... Mostly cloudy. A chance of showers and thunderstorms. Lows in the mid 70s. Highs in the lower 90s. Chance of rain 50%. Heat index values up to 105.
Friday... Mostly cloudy. A chance of showers and thunderstorms. Lows in the mid 70s. Highs in the lower 90s. Chance of rain 50%. Heat index values up to 105.
Friday Night... Partly cloudy in the evening, then clearing. Lows in the mid 70s. Heat index values up to 105 early in the evening.
Saturday... Sunny. A slight chance of showers and thunderstorms in the morning. Hot with highs in the mid 90s. Chance of rain 20%. Heat index values up to 110 in the afternoon.
Saturday Night... Mostly clear. Hot. Lows in the mid 70s. Highs in the mid 90s. Heat index values up to 110.
Sunday... Mostly clear. Hot. Lows in the mid 70s. Highs in the mid 90s. Heat index values up to 110.
Sunday Night... Mostly clear in the evening, then partly cloudy with a slight chance of showers and thunderstorms after midnight. Lows in the lower 70s. Chance of rain 20%. Heat index values up to 105 early in the evening.
POP = Probability of Precipitation
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