Illiopolis Weather Forecast

    • 20
    • 65

    Rain

    • 10
    • 25

    Chance Snow

    • 25
    • 30

    Chance Snow

    • 37
    • 55

    Mostly Sunny

    • 40
    • 64

    Partly Sunny

    • 43
    • 70

    Partly Sunny

Today 15 Mar Sangamon

Mostly cloudy with a chance of Thunderstorms. A chance of rain this Morning, then rain this afternoon. Windy with Highs in the mid 60s. South Winds 20 to 30 Mph with Gusts up to 45 Mph. Chance of rain 90 percent.

Tonight 15 Mar Sangamon

Rain with a slight chance of Thunderstorms in the evening. A chance of snow. Patchy blowing snow. Snow accumulation around an inch. Windy and much cooler with Lows around 19. West Winds 25 to 30 Mph with Gusts up to 45 Mph. Chance of precipitation near 100 percent.

Graph Plots Open in Graphs

  • Temperature Forecast NOAA

  • Temperature Real-Time

Illiopolis Temperature Statistics

March Temperature

Decatur Airport (19.3 miles)

  • Lowest 1 March, 2026

    24.7 °F

  • Average March

    49.3 °F

  • Highest 10 March, 2026

    80.1 °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

    55.4 °F

  • Average High 2021–2026

    65.4 °F
Get WillyWeather+ to remove ads