Summerville Weather Forecast

    • 68
    • 91

    Rain Showers

    • 61
    • 79

    Rain Showers

    • 64
    • 82

    Partly Sunny

    • 65
    • 87

    Slight Chance Thunderstorms

    • 68
    • 88

    Partly Sunny

    • 69
    • 92

    Chance Rain Showers

    • 64
    • 87

    Chance Rain Showers

Today 9 Sep Macoupin

Mostly sunny with a chance of Thunderstorms with a slight chance of Showers. Near steady temperature in the mid 80s. Temperature falling into the mid 80s late. Northwest Winds 5 to 10 Mph. Chance of rain 40 percent.

Tonight 9 Sep Macoupin

A chance of Thunderstorms. Showers likely. Lows in the upper 60s. North Winds 5 to 10 Mph. Chance of rain 70 percent.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Summerville Temperature Statistics

September Temperature

St. Louis Regional Airport (21.1 miles)

  • Lowest 7 September, 2026

    60.8 °F

  • Average September

    80.5 °F

  • Highest 5 September, 2026

    100.4 °F

Climate (2021–2026)

St. Louis Regional Airport (21.1 miles)

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  • Average Low 2021–2026

    46.6 °F

  • Average 2021–2026

    54.5 °F

  • Average High 2021–2026

    66.7 °F
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