Cupertino Weather Forecast

    • 63
    • 80

    Chance Rain

    • 61
    • 78

    Chance Rain

    • 59
    • 75

    Slight Chance Rain Showers

    • 58
    • 77

    Partly Sunny

    • 57
    • 80

    Mostly Sunny

    • 61
    • 82

    Partly Sunny

    • 58
    • 80

    Mostly Sunny

Today 8 Sep Santa Clara Valley Including San Jose

Mostly cloudy in the morning then becoming sunny. Highs around 80. West Winds 5 to 15 Mph.

Tonight 8 Sep Santa Clara Valley Including San Jose

Mostly clear in the evening then becoming mostly cloudy. A slight chance of rain in the Evening, then a chance of rain after midnight. Patchy fog after midnight. Lows in the lower 60s. West Winds 5 to 15 Mph in the evening. Becoming light.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Cupertino Temperature Statistics

September Temperature

San Jose, San Jose International Airport (6.2 miles)

  • Lowest 3 September, 2025

    60.1 °F

  • Average September

    69.3 °F

  • Highest 1 September, 2025

    89.1 °F

Climate (2020–Present)

San Jose, San Jose International Airport (6.2 miles)

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  • Average Low 2020–2025

    51.8 °F

  • Average 2020–2025

    61.5 °F

  • Average High 2020–2025

    72.6 °F
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