Third Napa Slough Weather Forecast

    • 47
    • 81

    Becoming Sunny

    • 46
    • 78

    Mostly Sunny

    • 50
    • 78

    Mostly Sunny

    • 49
    • 80

    Mostly Sunny

    • 47
    • 77

    Mostly Sunny

    • 51
    • 79

    Partly Sunny

Today 21 Mar North Bay Interior Valleys

Partly cloudy. Patchy dense fog in the morning. Highs in the 70s to 80s. West Winds 5 to 10 Mph increasing to 10 to 20 Mph in the afternoon.

Tonight 21 Mar North Bay Interior Valleys

Mostly clear. Lows in the mid 40s to upper 50s. Northwest Winds 10 to 20 Mph.

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  • Temperature Real-Time

Third Napa Slough Temperature Statistics

March Temperature

Napa, Napa County Airport (6.2 miles)

  • Lowest 5 March, 2026

    37.7 °F

  • Average March

    59.1 °F

  • Highest 18 March, 2026

    84.9 °F

Climate (2021–Present)

Napa, Napa County Airport (6.2 miles)

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  • Average Low 2021–2026

    47.2 °F

  • Average 2021–2026

    58.2 °F

  • Average High 2021–2026

    70.2 °F
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