Great Falls Weather Forecast

    • 45
    • 66

    Decreasing Clouds

    • 43
    • 62

    Mostly Sunny

    • 50
    • 72

    Chance Rain Showers

    • 50
    • 71

    Chance Rain Showers

    • 49
    • 72

    Partly Sunny

    • 49
    • 72

    Mostly Sunny

Today 15 Sep Cascade County below 5000ft

Partly sunny. Highs in the mid 60s. East Winds up to 10 Mph.

Tonight 15 Sep Cascade County below 5000ft

Mostly cloudy. Patchy fog early in the morning. Highs in the mid 60s. Lows 40 to 45. Northwest Winds up to 15 Mph.

Graph Plots Open in Graphs

  • Temperature Forecast NOAA

  • Temperature Real-Time

Great Falls Temperature Statistics

September Temperature

Great Falls, Great Falls International Airport (3.7 miles)

  • Lowest 12 September, 2026

    44.1 °F

  • Average September

    61.1 °F

  • Highest 1 September, 2026

    86.6 °F

Climate (2021–2026)

Great Falls, Great Falls International Airport (3.7 miles)

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

  • Average Low 2021–2026

    34.3 °F

  • Average 2021–2026

    46.9 °F

  • Average High 2021–2026

    59.1 °F
Get WillyWeather+ to remove ads