South - Lake Union Weather Forecast

    • 54
    • 67

    Becoming Sunny

    • 58
    • 83

    Mostly Sunny

    • 53
    • 74

    Partly Sunny

    • 54
    • 68

    Mostly Sunny

    • 56
    • 72

    Mostly Sunny

    • 56
    • 73

    Chance Rain

Today 15 Sep City of Seattle

Sunny. Highs in the mid 60s to lower 70s. Light wind becoming north to 10 Mph in the afternoon.

Tonight 15 Sep City of Seattle

Mostly clear. Lows in the mid 50s. North wind around 10 Mph.

Graph Plots Open in Graphs

  • Temperature Forecast NOAA

  • Temperature Real-Time

South - Lake Union Temperature Statistics

September Temperature

Boeing Field - King County International Airport (5.6 miles)

  • Lowest 11 September, 2025

    57 °F

  • Average September

    65.9 °F

  • Highest 3 September, 2025

    81 °F

Climate (2020–Present)

Boeing Field - King County International Airport (5.6 miles)

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

  • Average Low 2020–2025

    47 °F

  • Average 2020–2025

    54 °F

  • Average High 2020–2025

    61.4 °F
Get WillyWeather+ to remove ads