Third Napa Slough Weather Forecast

    • 49
    • 57

    Chance Rain

    • 50
    • 56

    Rain

    • 52
    • 53

    Rain

    • 52
    • 58

    Rain

    • 48
    • 55

    Rain Likely

    • 45
    • 53

    Rain Likely

Today 18 Dec North Bay Interior Valleys

Mostly cloudy. Patchy fog. A chance of rain. Highs in the 50s to lower 60s. South Winds around 5 Mph.

Tonight 18 Dec North Bay Interior Valleys

Cloudy. Areas of fog. A chance of rain. Lows in the mid 40s to lower 50s. South Winds 5 to 10 Mph.

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Third Napa Slough Temperature Statistics

December Temperature

Napa, Napa County Airport (6.2 miles)

  • Lowest 2 December, 2025

    37 °F

  • Average December

    44.5 °F

  • Highest 3 December, 2025

    66 °F

Climate (2020–Present)

Napa, Napa County Airport (6.2 miles)

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  • Average Low 2020–2025

    47 °F

  • Average 2020–2025

    58 °F

  • Average High 2020–2025

    70.1 °F
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