Napa Weather Forecast

    • 58
    • 87

    Mostly Sunny

    • 56
    • 84

    Partly Sunny

    • 52
    • 79

    Partly Sunny

    • 51
    • 75

    Partly Sunny

    • 51
    • 73

    Mostly Sunny

    • 53
    • 78

    Mostly Sunny

Today 23 Sep North Bay Interior Valleys

Partly cloudy in the morning then becoming sunny. Areas of fog in the morning. Highs in the upper 70s to lower 90s. West Winds 5 to 10 Mph.

Tonight 23 Sep North Bay Interior Valleys

Mostly clear in the evening then becoming partly cloudy. Lows in the lower 50s to mid 60s. West Winds 5 to 10 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

    65.9 °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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