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

Severe Thunderstorms and Heavy Rainfall for the Southwest; Heat Spreads Across the Center of the Nation

Moisture will continue to move into areas of the West. This will increase showers and thunderstorms coverage and intensity, with the risk of flash flooding and damaging wind gusts. Meanwhile, heat across the Southwest will expand into the center of the nation this weekend into early next week. Trends favor this heat will spread across the Ohio Valley, mid-Atlantic next week. Read More >

Current conditions at

Boeing Field - King County International Airport (KBFI)

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

Overcast

70°F

21°C

Humidity 52%
Wind Speed ESE 6 MPH
Barometer 30.04 in (1017.27 mb)
Dewpoint 52°F (11°C)
Visibility 10.00 mi
Last update 29 Aug 05:20 PM PDT
Extended Forecast for

Mercer Island WASimilar City Names

  • Tonight

    Tonight: Mostly cloudy, with a low around 55. Calm wind becoming south southeast around 6 mph in the evening.

    Low: 55 °F

    Mostly Cloudy

  • Sunday

    Sunday: Cloudy, then gradual clearing during the afternoon, with a high near 70. South wind around 5 mph becoming calm in the afternoon.

    High: 70 °F

    Clearing Late

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 55. Light north northeast wind.

    Low: 55 °F

    Partly Cloudy

  • Monday

    Monday: Mostly sunny, with a high near 75. Calm wind becoming north northwest around 6 mph in the afternoon.

    High: 75 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 57. North northwest wind around 6 mph becoming calm in the evening.

    Low: 57 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Partly sunny, with a high near 74.

    High: 74 °F

    Partly Sunny

  • Tuesday Night

    Tuesday Night: A 40 percent chance of rain. Mostly cloudy, with a low around 57.

    Low: 57 °F

    Chance Rain

  • Wednesday

    Wednesday: Rain likely before 11am, then showers likely and possibly a thunderstorm after 11am. Cloudy, with a high near 67.

    High: 67 °F

    Showers
    Likely

  • Wednesday Night

    Wednesday Night: Rain, mainly before 11pm. Mostly cloudy, with a low around 55.

    Low: 55 °F

    Rain

Detailed Forecast

Tonight
Mostly cloudy, with a low around 55. Calm wind becoming south southeast around 6 mph in the evening.
Sunday
Cloudy, then gradual clearing during the afternoon, with a high near 70. South wind around 5 mph becoming calm in the afternoon.
Sunday Night
Partly cloudy, with a low around 55. Light north northeast wind.
Monday
Mostly sunny, with a high near 75. Calm wind becoming north northwest around 6 mph in the afternoon.
Monday Night
Mostly cloudy, with a low around 57. North northwest wind around 6 mph becoming calm in the evening.
Tuesday
Partly sunny, with a high near 74.
Tuesday Night
A 40 percent chance of rain. Mostly cloudy, with a low around 57.
Wednesday
Rain likely before 11am, then showers likely and possibly a thunderstorm after 11am. Cloudy, with a high near 67.
Wednesday Night
Rain, mainly before 11pm. Mostly cloudy, with a low around 55.
Thursday
A chance of rain, then showers likely and possibly a thunderstorm after 11am. Mostly cloudy, with a high near 69.
Thursday Night
A chance of rain. Mostly cloudy, with a low around 54.
Friday
A chance of rain. Partly sunny, with a high near 70.
Friday Night
A chance of rain. Partly cloudy, with a low around 55.
Saturday
A slight chance of rain. Partly sunny, with a high near 72.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Mercer Island WASimilar City Names
 47.58°N 122.22°W (Elev. 118 ft)
Last Update:
12:20 pm PDT Aug 29, 2026
Forecast Valid:
5pm PDT Aug 29, 2026-6pm PDT Sep 5, 2026
 
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Additional Resources

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Chance of Precipitation