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City of O'Fallon, MOO'Fallon, MO 7-Day Night Weather Forecast
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O'Fallon, MO Weather Forecast
O'Fallon, MO Weather Forecast Date: 809 AM CDT Mon Oct 26 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... Partly sunny. Highs in the upper 70s. Southwest winds around 5 mph.
Tonight... Partly cloudy. Lows in the lower 50s. South winds around 5 mph.
Tuesday... Mostly cloudy. Highs in the mid 70s. South winds 5 to 10 mph.
Tuesday Night... Mostly cloudy. Lows in the lower 50s. South winds around 5 mph.
Wednesday... Mostly sunny. Highs in the upper 70s. South winds 5 to 10 mph.
Wednesday Night... Mostly clear. Lows in the mid 50s. Highs in the lower 80s.
Thursday... Mostly clear. Lows in the mid 50s. Highs in the lower 80s.
Thursday Night... Partly cloudy in the evening, then becoming mostly cloudy. Lows in the mid 50s.
Friday... Mostly cloudy. Highs around 80. Lows in the upper 50s.
Friday Night... Mostly cloudy. Highs around 80. Lows in the upper 50s.
Saturday... Mostly cloudy with a 40% chance of showers. Highs in the mid 70s.
Saturday Night... Mostly cloudy. A 50% chance of showers. Lows in the upper 50s. Highs in the mid 70s.
POP = Probability of Precipitation
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