Illiopolis Weather Forecast

    • 71
    • 87

    Chance Thunderstorms

    • 68
    • 83

    Rain Showers

    • 72
    • 90

    Chance Rain Showers

    • 74
    • 93

    Chance Rain Showers

    • 65
    • 91

    Rain Showers Likely

    • 65
    • 87

    Mostly Sunny

    • 65
    • 88

    Chance Thunderstorms

Today 7 Jun Sangamon

Partly sunny with a slight chance of Showers and Thunderstorms. Near steady temperature in the mid 80s. Southeast Winds 5 to 10 Mph with Gusts up to 20 Mph. Chance of rain 20 percent.

Tonight 7 Jun Sangamon

Mostly cloudy. A slight chance of Showers and Thunderstorms in the Evening, then a chance of Showers and Thunderstorms after midnight. Humid with Lows in the lower 70s. Southeast Winds 5 to 10 Mph. Chance of rain 50 percent.

Graph Plots Open in Graphs

  • Temperature Forecast NOAA

  • Temperature Real-Time

Illiopolis Temperature Statistics

June Temperature

Decatur Airport (19.3 miles)

  • Lowest 3 June, 2026

    51.7 °F

  • Average June

    71.2 °F

  • Highest 1 June, 2026

    86.6 °F

Climate (2021–Present)

Decatur Airport (19.3 miles)

Take a look at our website widgetsAvailable free! Find Out More

  • Average Low 2021–2026

    45.3 °F

  • Average 2021–2026

    55.5 °F

  • Average High 2021–2026

    65.6 °F
Get WillyWeather+ to remove ads