Johnstown Weather Forecast

    • 20
    • 42

    Mostly Sunny

    • 4
    • 33

    Mostly Cloudy

    • -1
    • 11

    Mostly Cloudy

    • 7
    • 13

    Chance Snow

    • 3
    • 18

    Partly Sunny

    • 6
    • 19

    Mostly Sunny

Today 21 Jan Cumberland

Mostly sunny. Not as cool with Highs in the lower 40s. Temperature falling into the upper 30s this afternoon. Southwest Winds 10 to 15 Mph with Gusts up to 30 Mph.

Tonight 21 Jan Cumberland

Mostly clear. Lows in the lower 20s. West Winds 10 to 15 Mph, becoming northwest after midnight. Gusts up to 30 Mph.

Graph Plots Open in Graphs

  • Temperature Forecast NOAA

  • Temperature Real-Time

Johnstown Temperature Statistics

January Temperature

Mattoon / Charleston, Coles County Memorial Airport (7.5 miles)

  • Lowest 19 January, 2026

    7 °F

  • Average January

    32.7 °F

  • Highest 8 January, 2026

    64 °F

Climate (2021–Present)

Mattoon / Charleston, Coles County Memorial Airport (7.5 miles)

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

  • Average Low 2021–2026

    45.8 °F

  • Average 2021–2026

    55.2 °F

  • Average High 2021–2026

    64.6 °F
Get WillyWeather+ to remove ads