Mount Vernon Weather Forecast

    • 64
    • 79

    Rain Showers

    • 56
    • 82

    Chance Rain Showers

    • 53
    • 74

    Mostly Sunny

    • 64
    • 82

    Slight Chance Rain Showers

    • 66
    • 85

    Chance Rain Showers

    • 61
    • 83

    Rain Showers Likely

Today 12 Sep Knox

Showers likely with a slight chance of Thunderstorms this Morning, then Showers with a chance of Thunderstorms this afternoon. Highs in the upper 70s. South Winds 5 to 10 Mph. Chance of rain 90 percent.

Tonight 12 Sep Knox

Mostly cloudy. A chance of Showers and Thunderstorms in the Evening, then a slight chance of Showers after midnight. Humid with Lows in the mid 60s. Southwest Winds around 5 Mph. Chance of rain 50 percent.

Graph Plots Open in Graphs

  • Temperature Forecast NOAA

  • Temperature Real-Time

Mount Vernon Temperature Statistics

September Temperature

Knox County Airfield (4.3 miles)

  • Lowest 7 September, 2026

    57.2 °F

  • Average September

    73.8 °F

  • Highest 2 September, 2026

    91.4 °F

Climate (2021–2026)

Knox County Airfield (4.3 miles)

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

  • Average Low 2021–2026

    43.4 °F

  • Average 2021–2026

    52.3 °F

  • Average High 2021–2026

    61.7 °F
Get WillyWeather+ to remove ads