Napa Weather Forecast

    • 53
    • 79

    Increasing Clouds

    • 54
    • 73

    Mostly Cloudy

    • 54
    • 76

    Partly Sunny

    • 55
    • 83

    Mostly Sunny

    • 54
    • 82

    Partly Sunny

    • 54
    • 79

    Partly Sunny

    • 55
    • 80

    Mostly Sunny

Today 15 Sep North Bay Interior Valleys

Sunny. Highs in the lower 70s to mid 80s. Southwest Winds 10 to 15 Mph.

Tonight 15 Sep North Bay Interior Valleys

Mostly clear in the evening then becoming partly cloudy. Patchy fog after midnight. Lows in the 40s to upper 50s. Southwest Winds 10 to 15 Mph.

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Napa Temperature Statistics

September Temperature

Napa, Napa County Airport (6.2 miles)

  • Lowest 6 September, 2026

    45.6 °F

  • Average September

    67.2 °F

  • Highest 9 September, 2026

    99.6 °F

Climate (2021–2026)

Napa, Napa County Airport (6.2 miles)

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  • Average Low 2021–2026

    47.3 °F

  • Average 2021–2026

    58.5 °F

  • Average High 2021–2026

    70.3 °F
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