Grantham Weather Forecast

    • 42
    • 45

    Rain Showers

    • 23
    • 51

    Chance Rain Showers

    • 34
    • 40

    Mostly Cloudy

    • 24
    • 44

    Mostly Sunny

    • 26
    • 37

    Mostly Cloudy

    • 32
    • 43

    Mostly Cloudy

Today 18 Dec Cumberland

Patchy freezing fog in the morning. Partly sunny in the Morning, then mostly cloudy with a chance of rain in the afternoon. Highs in the mid 40s. Southeast Winds 5 to 10 Mph. Chance of precipitation 40 percent.

Tonight 18 Dec Cumberland

Partly cloudy. Areas of freezing fog. Lows in the mid 20s. Light and variable Winds.

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Grantham Temperature Statistics

December Temperature

Harrisburg, Capital City Airport (8.1 miles)

  • Lowest 9 December, 2025

    10 °F

  • Average December

    29.4 °F

  • Highest 1 December, 2025

    41 °F

Climate (2020–Present)

Harrisburg, Capital City Airport (8.1 miles)

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  • Average Low 2020–2025

    47.8 °F

  • Average 2020–2025

    57.1 °F

  • Average High 2020–2025

    66.5 °F
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