Collinsville Weather Forecast

    • 74
    • 92

    Mostly Sunny

    • 74
    • 91

    Chance Thunderstorms

    • 75
    • 91

    Chance Thunderstorms

    • 76
    • 94

    Mostly Sunny

    • 75
    • 93

    Mostly Sunny

    • 76
    • 96

    Slight Chance Thunderstorms

Today 15 Jul Madison

Sunny. Highs in the lower 90s. Northeast Winds around 5 Mph.

Tonight 15 Jul Madison

Partly cloudy in the Evening, then becoming mostly clear. Humid with Lows in the lower 70s. Southeast Winds around 5 Mph in the Evening, becoming light and variable.

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Collinsville Temperature Statistics

July Temperature

Belleville, Scott AFB/MidAmerica Airport (10.6 miles)

  • Lowest 13 July, 2026

    70 °F

  • Average July

    79.9 °F

  • Highest 2 July, 2026

    95.5 °F

Climate (2021–2026)

Belleville, Scott AFB/MidAmerica Airport (10.6 miles)

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  • Average Low 2021–2026

    47.9 °F

  • Average 2021–2026

    57.9 °F

  • Average High 2021–2026

    68.1 °F
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