Second Napa Slough Weather Forecast

    • 58
    • 87

    Sunny

    • 57
    • 88

    Sunny

    • 59
    • 88

    Mostly Sunny

    • 60
    • 78

    Chance Rain Showers

    • 58
    • 78

    Slight Chance Rain Showers

    • 58
    • 79

    Mostly Sunny

    • 57
    • 79

    Mostly Sunny

Today 15 Sep North Bay Interior Valleys

Sunny. Highs in the 80s to 90s. South Winds 5 to 10 Mph.

Tonight 15 Sep North Bay Interior Valleys

Clear. Lows in the lower 50s to mid 60s. West Winds 5 to 10 Mph.

Graph Plots Open in Graphs

  • Temperature Forecast NOAA

  • Temperature Real-Time

Second Napa Slough Temperature Statistics

September Temperature

Napa, Napa County Airport (6.8 miles)

  • Lowest 3 September, 2025

    52 °F

  • Average September

    65.7 °F

  • Highest 1 September, 2025

    89.1 °F

Climate (2020–Present)

Napa, Napa County Airport (6.8 miles)

Take a look at our website widgetsAvailable free! Find Out More

  • Average Low 2020–2025

    46.9 °F

  • Average 2020–2025

    58.1 °F

  • Average High 2020–2025

    70.5 °F
Get WillyWeather+ to remove ads