St. Charles Airport Weather Forecast
- 77
- 94
Isolated Thunderstorms
- 78
- 97
Hot
- 77
- 97
Slight Chance Thunderstorms
- 75
- 94
Slight Chance Thunderstorms
- 76
- 94
Slight Chance Thunderstorms
- 76
- 95
Mostly Sunny
- 77
- 95
Mostly Sunny
Today 22 Jul St. Charles
Partly sunny with isolated Showers and Thunderstorms. Near steady temperature in the lower 90s. Southeast Winds 5 to 10 Mph. Chance of rain 20 percent. Heat index Values up to 110.
Tonight 22 Jul St. Charles
Partly cloudy. Isolated Showers and Thunderstorms this evening. Lows in the mid 70s. Southeast Winds around 5 Mph. Chance of rain 20 percent. Heat index Values up to 107 early this evening.
St. Charles Airport Temperature Statistics
July Temperature
St. Charles, St. Charles County Smartt Airport (6.2 miles)
Lowest 2 July, 2025
65.6 °FAverage July
80.3 °FHighest 16 July, 2025
94.6 °F
Climate (2020–Present)
St. Charles, St. Charles County Smartt Airport (6.2 miles)
Average Low 2020–2025
47.3 °FAverage 2020–2025
57.6 °FAverage High 2020–2025
68.3 °F