Castro Valley Weather Forecast

    • 54
    • 70

    Rain

    • 51
    • 64

    Rain Showers

    • 49
    • 66

    Chance Rain

    • 49
    • 70

    Partly Sunny

    • 52
    • 71

    Partly Sunny

    • 53
    • 70

    Partly Sunny

Today 20 Apr San Francisco Bay Shoreline

Mostly cloudy. A chance of rain. Highs in the upper 60s. South Winds 10 to 20 Mph.

Tonight 20 Apr San Francisco Bay Shoreline

Rain. Lows in the mid 50s. Southwest Winds 10 to 20 Mph. Becoming south 5 to 10 Mph after midnight.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Castro Valley Temperature Statistics

April Temperature

Hayward, Hayward Air Terminal (3.1 miles)

  • Lowest 3 April, 2026

    44.7 °F

  • Average April

    60.5 °F

  • Highest 5 April, 2026

    82.7 °F

Climate (2021–Present)

Hayward, Hayward Air Terminal (3.1 miles)

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  • Average Low 2021–2026

    52.3 °F

  • Average 2021–2026

    59.6 °F

  • Average High 2021–2026

    69.1 °F
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