Bethalto Weather Forecast
- 62
- 81
Mostly Sunny
- 65
- 85
Mostly Sunny
- 60
- 86
Partly Sunny
- 55
- 79
Mostly Sunny
- 53
- 75
Partly Sunny
- 54
- 74
Partly Sunny
Today 21 Aug Madison
Mostly sunny. Highs in the lower 80s. Northeast Winds 5 to 10 Mph.
Tonight 21 Aug Madison
Partly cloudy. Lows in the mid 60s. Northeast Winds 5 to 10 Mph.
Bethalto Temperature Statistics
August Temperature
St. Louis Regional Airport (1.2 miles)
Lowest 3 August, 2025
56.7 °FAverage August
74.6 °FHighest 16 August, 2025
95 °F
Climate (2020–Present)
St. Louis Regional Airport (1.2 miles)
Average Low 2020–2025
46.1 °FAverage 2020–2025
53.9 °FAverage High 2020–2025
66 °F