Grantham Weather Forecast

    • 47
    • 71

    Rain Showers

    • 42
    • 64

    Partly Sunny

    • 47
    • 64

    Chance Rain Showers

    • 50
    • 68

    Slight Chance Thunderstorms

    • 51
    • 76

    Rain Showers Likely

    • 44
    • 64

    Slight Chance Rain Showers

Today 6 May Cumberland

Showers this Morning, then a chance of Showers with a slight chance of Thunderstorms this afternoon. Not as warm with Highs around 70. Southwest Winds 5 to 10 Mph with Gusts up to 25 Mph. Chance of rain near 100 percent.

Tonight 6 May Cumberland

Mostly cloudy. Cooler with Lows in the mid 40s. Northwest Winds 5 to 10 Mph.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Grantham Temperature Statistics

May Temperature

Harrisburg, Capital City Airport (8.1 miles)

  • Lowest 1 May, 2026

    39 °F

  • Average May

    53.5 °F

  • Highest 4 May, 2026

    73.9 °F

Climate (2021–Present)

Harrisburg, Capital City Airport (8.1 miles)

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  • Average Low 2021–2026

    47.5 °F

  • Average 2021–2026

    56.9 °F

  • Average High 2021–2026

    66.3 °F
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