Janesville Weather Forecast

    • 60
    • 81

    Mostly Cloudy

    • 57
    • 78

    Mostly Cloudy

    • 59
    • 76

    Chance Rain Showers

    • 58
    • 79

    Mostly Sunny

    • 56
    • 78

    Mostly Sunny

    • 57
    • 78

    Mostly Sunny

Today 29 May Cumberland

Partly sunny. Highs in the lower 80s. East Winds 5 to 10 Mph.

Tonight 29 May Cumberland

Mostly cloudy. Lows in the lower 60s. East Winds around 5 Mph.

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  • Temperature Real-Time

Janesville Temperature Statistics

May Temperature

Mattoon / Charleston, Coles County Memorial Airport (6.8 miles)

  • Lowest 7 May, 2026

    38.6 °F

  • Average May

    61.7 °F

  • Highest 17 May, 2026

    83.6 °F

Climate (2021–Present)

Mattoon / Charleston, Coles County Memorial Airport (6.8 miles)

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  • Average Low 2021–2026

    45.9 °F

  • Average 2021–2026

    55.4 °F

  • Average High 2021–2026

    65 °F
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