Grass Valley Lake Weather Forecast

    • 60
    • 76

    Becoming Sunny

    • 62
    • 79

    Sunny

    • 64
    • 83

    Sunny

    • 66
    • 86

    Sunny

    • 65
    • 87

    Sunny

    • 64
    • 84

    Mostly Sunny

Today 5 Jul San Bernardino County Mountains

Mostly sunny in the morning. Becoming partly cloudy. Highs 71 to 81 above 6000 feet to 76 to 86 below 6000 feet. Areas of Winds south 10 to 15 Mph. Gusts to 30 Mph in the afternoon.

Tonight 5 Jul San Bernardino County Mountains

Mostly clear. Lows 47 to 57 above 6000 feet to 55 to 65 below 6000 feet. Areas of Winds south 10 to 15 Mph. Gusts to 25 Mph in the evening.

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Grass Valley Lake Temperature Statistics

July Temperature

San Bernardino Intl. Airport (11.8 miles)

  • Lowest 2 July, 2026

    59 °F

  • Average July

    67.4 °F

  • Highest 2 July, 2026

    86 °F

Climate (2021–2026)

San Bernardino Intl. Airport (11.8 miles)

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  • Average Low 2021–2026

    54.2 °F

  • Average 2021–2026

    63.2 °F

  • Average High 2021–2026

    80.4 °F
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