National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

Boeing Field - King County International Airport (KBFI)

Lat: 47.54548°NLon: 122.3147°WElev: 20.0ft.

Clear

46°F

8°C

Humidity 87%
Wind Speed SE 3 MPH
Barometer 30.18 in (1022.01 mb)
Dewpoint 43°F (6°C)
Visibility 10.00 mi
Last update 20 Nov 06:35 PM PST
Extended Forecast for

Mercer Island WA

  • Tonight

    Tonight: Partly cloudy, with a low around 42. Light south southeast wind.

    Low: 42 °F

    Partly Cloudy

  • Friday

    Friday: A 20 percent chance of rain after noon. Partly sunny, with a high near 54. South wind around 6 mph.

    High: 54 °F

    Partly Sunny
    then Slight
    Chance Rain

  • Friday Night

    Friday Night: A 30 percent chance of rain. Mostly cloudy, with a low around 48. South wind around 6 mph.

    Low: 48 °F

    Chance Rain

  • Saturday

    Saturday: A 40 percent chance of rain. Mostly cloudy, with a high near 57. South wind around 6 mph.

    High: 57 °F

    Chance Rain

  • Saturday Night

    Saturday Night: Rain, mainly after 10pm. Low around 49. South wind around 7 mph. Chance of precipitation is 80%. New precipitation amounts of less than a tenth of an inch possible.

    Low: 49 °F

    Rain

  • Sunday

    Sunday: Rain. High near 53. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.

    High: 53 °F

    Rain

  • Sunday Night

    Sunday Night: Rain likely before 8pm, then showers likely after 8pm. Mostly cloudy, with a low around 42. Chance of precipitation is 70%.

    Low: 42 °F

    Rain Likely

  • Monday

    Monday: Showers likely, mainly before 10am. Partly sunny, with a high near 50.

    High: 50 °F

    Showers
    Likely

  • Monday Night

    Monday Night: A slight chance of showers before 10pm, then a slight chance of rain after 4am. Mostly cloudy, with a low around 40.

    Low: 40 °F

    Slight Chance
    Showers

Detailed Forecast

Tonight
Partly cloudy, with a low around 42. Light south southeast wind.
Friday
A 20 percent chance of rain after noon. Partly sunny, with a high near 54. South wind around 6 mph.
Friday Night
A 30 percent chance of rain. Mostly cloudy, with a low around 48. South wind around 6 mph.
Saturday
A 40 percent chance of rain. Mostly cloudy, with a high near 57. South wind around 6 mph.
Saturday Night
Rain, mainly after 10pm. Low around 49. South wind around 7 mph. Chance of precipitation is 80%. New precipitation amounts of less than a tenth of an inch possible.
Sunday
Rain. High near 53. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.
Sunday Night
Rain likely before 8pm, then showers likely after 8pm. Mostly cloudy, with a low around 42. Chance of precipitation is 70%.
Monday
Showers likely, mainly before 10am. Partly sunny, with a high near 50.
Monday Night
A slight chance of showers before 10pm, then a slight chance of rain after 4am. Mostly cloudy, with a low around 40.
Tuesday
A chance of rain, mainly after 10am. Mostly cloudy, with a high near 49.
Tuesday Night
Rain likely. Mostly cloudy, with a low around 41.
Wednesday
Rain likely. Cloudy, with a high near 50.
Wednesday Night
Rain likely. Mostly cloudy, with a low around 44.
Thanksgiving Day
A chance of rain. Mostly cloudy, with a high near 51.
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ABOUT THIS FORECAST

 
Point Forecast:
Mercer Island WA
 47.6°N 122.22°W (Elev. 3 ft)
Last Update:
1:25 pm PST Nov 20, 2025
Forecast Valid:
6pm PST Nov 20, 2025-6pm PST Nov 27, 2025
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation