Second Napa Slough Weather Forecast

    • 47
    • 51

    Areas Fog

    • 55
    • 58

    Rain

    • 48
    • 60

    Rain Likely

    • 52
    • 57

    Chance Rain

    • 51
    • 57

    Rain

    • 48
    • 56

    Rain Likely

    • 49
    • 54

    Rain Likely

Today 15 Dec North Bay Interior Valleys

Mostly cloudy. Highs in the mid 40s to upper 50s. South Winds 5 to 10 Mph.

Tonight 15 Dec North Bay Interior Valleys

Mostly cloudy. Areas of fog in the evening. Patchy fog after midnight. A slight chance of rain after midnight. Lows in the mid 40s to lower 50s. West Winds 10 to 15 Mph.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Second Napa Slough Temperature Statistics

December Temperature

Napa, Napa County Airport (6.8 miles)

  • Lowest 2 December, 2025

    37 °F
  • Average December

    44.7 °F
  • Highest 3 December, 2025

    66 °F

Climate (2020–Present)

Napa, Napa County Airport (6.8 miles)

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  • Average Low 2020–2025

    47 °F
  • Average 2020–2025

    58.1 °F
  • Average High 2020–2025

    70.1 °F
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