10-Day Weather Forecast - O'Fallon, MO

Partly sunny. Highs in the upper 30s. South winds 5 to 10 mph.

Partly cloudy. Not as cool with lows in the upper 20s. West winds 5 to 10 mph.

Mostly sunny. Highs in the upper 40s. Northwest winds 15 to 20 mph with gusts up to 30 mph.

Partly cloudy. Lows in the mid 20s. North winds 5 to 10 mph.

Mostly sunny. Cooler with highs in the upper 30s.

Mostly cloudy. Lows in the upper 20s.

Partly sunny in the morning then clearing. Not as cool with highs in the mid 50s.

Mostly clear. Lows in the lower 30s. Highs in the upper 50s.

Mostly clear. Lows in the lower 30s. Highs in the upper 50s.

Mostly clear. Lows around 40.

Mostly sunny in the morning then becoming mostly cloudy. A 20 percent chance of rain. Highs in the lower 60s.

Mostly cloudy. A chance of rain mainly in the evening. Lows in the lower 40s. Chance of rain 30 percent.

Sunny with a 20 percent chance of rain. Highs in the mid 50s.

Partly cloudy. Low temperature around 43F. Dew point will be around 37F with an average humidity of 71%. Winds will be 1 mph from the SE.

Cloudy with a slight chance of rain. Chance of precipitation 30%. High temperature around 50F. Dew point will be around 37F with an average humidity of 67%. Winds will be 1 mph from the S.

Cloudy with a chance of rain. Chance of precipitation 45%. Low temperature around 42F. Dew point will be around 37F with an average humidity of 76%. Winds will be 1 mph from the E.

Cloudy with a slight chance of rain. Chance of precipitation 30%. High temperature around 52F. Dew point will be around 38F with an average humidity of 68%. Winds will be 1 mph from the E.

Cloudy with a slight chance of rain. Chance of precipitation 25%. Low temperature around 41F. Dew point will be around 36F with an average humidity of 72%. Winds will be 1 mph from the N.