Weather WorldHalfmoon Lake, IL 7-Day Night Weather Forecast
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Halfmoon Lake, IL Weather Forecast
Halfmoon Lake, IL Weather Forecast Date: 903 AM CDT Sun Oct 11 2026
The area/counties/county of: Madison County Il, including the cities of: Alton, Edwardsville, Belleville, Cahokia, Saint Charles, and Saint Louis.or toggle through each period.
Today... Sunny. Highs in the upper 80s. Southwest winds around 5 mph.
Tonight... Mostly clear. Not as cool with lows in the mid 60s. South winds around 5 mph.
Columbus Day... Sunny. Highs in the mid 90s. Southwest winds 10 to 15 mph.
Monday Night... Clear. Lows around 70. Southwest winds 5 to 10 mph.
Tuesday... Sunny. Highs in the mid 90s. Southwest winds 5 to 10 mph.
Tuesday Night... Partly cloudy in the evening, then becoming mostly cloudy. A chance of showers and thunderstorms. Lows around 70. Chance of rain 50%.
Wednesday... A slight chance of thunderstorms. Showers, cooler with highs in the lower 80s. Chance of rain 80%.
Wednesday Night... A slight chance of thunderstorms. A chance of showers in the evening, then showers likely after midnight. Lows in the lower 60s. Chance of rain 70%.
Thursday... Showers likely with a slight chance of thunderstorms in the morning, then showers likely with a chance of thunderstorms in the afternoon. Highs in the upper 70s. Chance of rain 70%.
Thursday Night... Mostly cloudy with a chance of showers and thunderstorms. Lows in the mid 50s. Chance of rain 40%.
Friday... Partly sunny. A slight chance of showers in the morning. Cooler with highs in the upper 60s. Chance of rain 20%.
Friday Night... Partly cloudy. Cooler with lows in the lower 40s.
POP = Probability of Precipitation
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