Grand River Weather Forecast

    • 59
    • 79

    Decreasing Clouds

    • 63
    • 83

    Mostly Sunny

    • 67
    • 87

    Partly Sunny

    • 71
    • 90

    Mostly Sunny

    • 72
    • 92

    Partly Sunny

    • 70
    • 92

    Slight Chance Thunderstorms

Today 4 Aug Decatur

Mostly sunny. Highs in the upper 70s. East Winds around 5 Mph.

Tonight 4 Aug Decatur

Mostly clear. Lows in the upper 50s. East Winds around 5 Mph.

Graph Plots Open in Graphs

  • Temperature Forecast NOAA

  • Temperature Real-Time

Grand River Temperature Statistics

August Temperature

Lamoni, Lamoni Municipal Airport (13 miles)

  • Lowest 1 August, 2025

    57.9 °F

  • Average August

    65.1 °F

  • Highest 1 August, 2025

    73.9 °F

Climate (2020–Present)

Lamoni, Lamoni Municipal Airport (13 miles)

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

  • Average Low 2020–2025

    43.2 °F

  • Average 2020–2025

    53 °F

  • Average High 2020–2025

    63.1 °F
Get WillyWeather+ to remove ads