Illiopolis Weather Forecast

    • 64
    • 85

    Sunny

    • 66
    • 86

    Sunny

    • 69
    • 89

    Sunny

    • 70
    • 90

    Sunny

    • 70
    • 90

    Mostly Sunny

    • 71
    • 89

    Mostly Sunny

    • 69
    • 88

    Slight Chance Thunderstorms

Today 12 Jul Sangamon

Sunny. Near steady temperature in the mid 80s. Northeast Winds around 10 Mph.

Tonight 12 Jul Sangamon

Clear. Lows in the mid 60s. Northeast Winds around 5 Mph.

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  • Temperature Real-Time

Illiopolis Temperature Statistics

July Temperature

Decatur Airport (19.3 miles)

  • Lowest 8 July, 2026

    65.6 °F

  • Average July

    79.4 °F

  • Highest 2 July, 2026

    93.7 °F

Climate (2021–2026)

Decatur Airport (19.3 miles)

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  • Average Low 2021–2026

    45.3 °F

  • Average 2021–2026

    55.5 °F

  • Average High 2021–2026

    65.6 °F
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