Weather WorldHalfmoon Lake, IL 7-Day Night Weather Forecast
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Halfmoon Lake, IL Weather Forecast
Halfmoon Lake, IL Weather Forecast Date: 402 AM CDT Thu Oct 15 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... Mostly cloudy this morning, then becoming partly sunny. Patchy fog this morning. Showers likely with a chance of thunderstorms. Highs in the lower 80s. Southeast winds 5 to 10 mph, becoming south with gusts up to 20 mph this afternoon. Chance of rain 70%.
Tonight... A chance of thunderstorms in the evening. Numerous showers. Much cooler with lows in the upper 40s. West winds 10 to 15 mph, becoming northwest 15 to 20 mph after midnight. Chance of rain 70%.
Friday... Partly sunny. Much cooler. Less humid with highs in the upper 50s. Northwest winds 15 to 20 mph with gusts up to 30 mph.
Friday Night... Mostly cloudy in the evening, then becoming partly cloudy. Lows in the upper 30s. North winds 15 to 20 mph.
Saturday... Sunny. Highs around 60. North winds 5 to 10 mph.
Saturday Night... Clear. Lows in the upper 30s. Highs in the upper 60s.
Sunday... Clear. Lows in the upper 30s. Highs in the upper 60s.
Sunday Night... Mostly clear. Lows around 40.
Monday... Partly cloudy. Highs in the lower 70s. Lows in the lower 40s.
Monday Night... Partly cloudy. Highs in the lower 70s. Lows in the lower 40s.
Tuesday... Mostly clear. Highs in the mid 70s. Lows in the mid 40s.
POP = Probability of Precipitation
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