Chambersburg Weather Forecast

    • 53
    • 64

    Rain Showers Likely

    • 52
    • 68

    Mostly Cloudy

    • 51
    • 66

    Mostly Cloudy

    • 53
    • 68

    Chance Rain Showers

    • 53
    • 67

    Chance Rain Showers

    • 53
    • 70

    Partly Sunny

Today 22 Sep Mercer

Cloudy with a 50 percent chance of Showers. Highs in the lower 60s. Northeast Winds around 10 Mph with Gusts up to 20 Mph.

Tonight 22 Sep Mercer

Mostly cloudy. Lows in the lower 50s. Northeast Winds 10 to 15 Mph.

Graph Plots Open in Graphs

  • Temperature Forecast NOAA

  • Temperature Real-Time

Chambersburg Temperature Statistics

September Temperature

Trenton, Mercer County Airport (5.6 miles)

  • Lowest 15 September, 2026

    51.7 °F

  • Average September

    72.2 °F

  • Highest 1 September, 2026

    88.6 °F

Climate (2021–2026)

Trenton, Mercer County Airport (5.6 miles)

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

  • Average Low 2021–2026

    46 °F

  • Average 2021–2026

    55.3 °F

  • Average High 2021–2026

    64.5 °F
Get WillyWeather+ to remove ads