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Observed 12:10 AM PDT at KBFI

Mercer Island, WA weather

Clear and 43°6°.

Today: low 44°7° (likely 39°4° to 44°7°), high 56°13° (likely 54°12° to 59°15°).

Mostly agree

Now 43°6°

Clear · Feels like 39°4°

Wind
7 mph11 km/h
From the south-southeast. Up to 7 mph11 km/h through 12 PM
Dew point
37°3°
Comfortable
UV tomorrow
2Low
Low all day (peak 2)
Air quality
60Moderate
PM2.5 (fine particles) · tomorrow good
Pressure
30.33 inHg1027 hPa
Falling slowly · −0.03 inHg−0.9 hPa next 3 h

Next 2 hours

No precipitation expected in the next 2 hours.

Next 48 hours

5°3° cooler than this time yesterday (48°9° then, 43°6° now)

Good hours for
  • Low 44°7° today at 6 AM
  • High 56°13° today at 4 PM
  • Rain tomorrow 5 AM–tomorrow night 11 PM (60%, 0.54 in14 mm)
  1. TonightNear 46°8° · Partly cloudy
  2. This morningNear 46°8° · Mostly cloudy
  3. This afternoonUp to 56°13° by 4 PM · Cloudy
  4. TonightDown to 49°9° by 5 AM · Rain 5–6 AM (60%)
  5. Tomorrow morningNear 49°9° · Rain all morning (60%)
  6. Tomorrow afternoonUp to 57°14° by 4 PM · Rain all afternoon (60%)
  7. Tomorrow nightNear 54°12° · Rain 6–11 PM (30%)
Hourly forecast, next 48 hours, in the place's local time
HourConditionsTemperatureFeels likePrecipitationWindHumidityCloud coverUV index
Sat 12aClear47°8° (likely 41°5° to 47°8°)47°8°0%2 mph3 km/h from SE, gusts 3 mph5 km/h89%9%0
Sat 1aPartly cloudy46°8° (likely 40°4° to 46°8°)46°8°0%2 mph3 km/h from SE, gusts 4 mph7 km/h90%26%0
Sat 2aCloudy46°8° (likely 39°4° to 46°8°)45°7°0%3 mph5 km/h from SE, gusts 5 mph8 km/h89%67%0
Sat 3aCloudy46°8° (likely 39°4° to 46°8°)46°8°0%2 mph3 km/h from SE, gusts 5 mph8 km/h89%78%0
Sat 4aCloudy46°8° (likely 40°4° to 46°8°)46°8°0%2 mph3 km/h from SE, gusts 4 mph7 km/h89%78%0
Sat 5aCloudy45°7° (likely 40°4° to 45°7°)45°7°0%2 mph3 km/h from SSE, gusts 3 mph5 km/h89%78%0
Sat 6aCloudy44°7° (likely 40°4° to 44°7°)44°7°0%2 mph3 km/h from SSE, gusts 4 mph6 km/h90%79%0
Sat 7aCloudy45°7° (likely 39°4° to 45°7°)45°7°0%2 mph3 km/h from SSE, gusts 4 mph7 km/h89%79%0
Sat 8aCloudy44°7° (likely 39°4° to 44°7°)44°7°0%2 mph3 km/h from SSE, gusts 4 mph7 km/h89%76%0
Sat 9aCloudy45°7° (likely 42°6° to 45°7°)45°7°5%2 mph3 km/h from SSE, gusts 4 mph7 km/h89%80%0
Sat 10aCloudy45°7° (likely 45°7° to 48°9°)45°7°5%1 mph2 km/h from S, gusts 6 mph10 km/h87%80%1
Sat 11aCloudy47°8° (likely 47°8° to 51°11°)47°8°5%1 mph2 km/h from SSW, gusts 7 mph12 km/h82%82%2
Sat 12pCloudy49°9° (likely 49°9° to 54°12°)49°9°5%1 mph2 km/h from SSW, gusts 7 mph11 km/h80%99%2
Sat 1pCloudy52°11° (likely 52°11° to 56°13°)52°11°5%1 mph2 km/h from SW, gusts 7 mph11 km/h75%82%2
Sat 2pCloudy54°12° (likely 53°12° to 58°14°)54°12°5%2 mph3 km/h from SW, gusts 7 mph11 km/h71%80%2
Sat 3pCloudy54°12° (likely 54°12° to 59°15°)54°12°5%2 mph3 km/h from SW, gusts 7 mph11 km/h69%79%2
Sat 4pCloudy56°13° (likely 54°12° to 59°15°)56°13°5%2 mph3 km/h from SW, gusts 7 mph11 km/h66%94%1
Sat 5pCloudy55°13° (likely 53°12° to 59°15°)55°13°0%1 mph2 km/h from W, gusts 5 mph8 km/h68%90%1
Sat 6pCloudy54°12° (likely 52°11° to 57°14°)54°12°0%1 mph2 km/h from S, gusts 5 mph8 km/h71%85%0
Sat 7pCloudy53°12° (likely 50°10° to 55°13°)53°12°0%1 mph2 km/h from SE, gusts 5 mph8 km/h72%81%0
Sat 8pCloudy52°11° (likely 49°9° to 53°12°)52°11°5%2 mph3 km/h from S, gusts 4 mph6 km/h73%79%0
Sat 9pCloudy52°11° (likely 49°9° to 52°11°)52°11°5%2 mph3 km/h from SSE, gusts 4 mph6 km/h74%93%0
Sat 10pCloudy51°11° (likely 48°9° to 52°11°)51°11°5%2 mph3 km/h from SSE, gusts 4 mph7 km/h76%92%0
Sat 11pCloudy51°11° (likely 47°8° to 51°11°)51°11°5%, 0.02 in0.5 mm2 mph3 km/h from SSE, gusts 4 mph6 km/h76%97%0
Sun 12aCloudy50°10° (likely 47°8° to 51°11°)50°10°5%, 0.02 in0.5 mm2 mph3 km/h from SE, gusts 5 mph8 km/h79%95%0
Sun 1aCloudy50°10° (likely 46°8° to 51°11°)50°10°5%, 0.02 in0.5 mm2 mph3 km/h from SSE, gusts 6 mph9 km/h80%66%0
Sun 2aMostly cloudy50°10° (likely 45°7° to 51°11°)49°9°10%, 0.02 in0.5 mm3 mph5 km/h from SSE, gusts 6 mph9 km/h80%69%0
Sun 3aMostly cloudy50°10° (likely 44°7° to 51°11°)49°9°10%, 0.02 in0.5 mm3 mph5 km/h from ESE, gusts 6 mph9 km/h80%73%0
Sun 4aRain50°10° (likely 43°6° to 50°10°)50°10°20%, 0.02 in0.5 mm2 mph3 km/h from SSE, gusts 5 mph8 km/h81%89%0
Sun 5aCloudy49°9° (likely 42°6° to 50°10°)48°9°60%, 0.06 in1.5 mm3 mph5 km/h from W, gusts 2 mph3 km/h82%100%0
Sun 6aRain49°9° (likely 41°5° to 50°10°)48°9°50%, 0.06 in1.5 mm3 mph5 km/h from W, gusts 4 mph7 km/h84%98%0
Sun 7aRain48°9° (likely 42°6° to 50°10°)47°8°20%, 0.06 in1.5 mm3 mph5 km/h from W, gusts 5 mph8 km/h85%100%0
Sun 8aRain49°9° (likely 42°6° to 49°9°)48°9°20%, 0.06 in1.5 mm3 mph5 km/h from NE, gusts 6 mph10 km/h86%65%0
Sun 9aRain48°9° (likely 44°7° to 50°10°)47°8°20%, 0.06 in1.5 mm3 mph5 km/h from NE, gusts 5 mph8 km/h90%98%0
Sun 10aRain48°9° (likely 48°9° to 51°11°)47°8°30%, 0.06 in1.5 mm3 mph5 km/h from NE, gusts 4 mph7 km/h93%99%1
Sun 11aRain49°9° (likely 49°9° to 55°13°)49°9°60%, 0.02 in0.5 mm2 mph3 km/h from E, gusts 5 mph8 km/h92%64%1
Sun 12pRain51°11° (likely 50°10° to 56°13°)51°11°60%, 0.02 in0.5 mm2 mph3 km/h from E, gusts 5 mph8 km/h90%56%2
Sun 1pCloudy53°12° (likely 50°10° to 58°14°)53°12°60%, 0.02 in0.5 mm2 mph3 km/h from E, gusts 6 mph10 km/h85%99%2
Sun 2pCloudy55°13° (likely 50°10° to 59°15°)55°13°20%, 0.02 in0.5 mm3 mph5 km/h from ENE, gusts 5 mph8 km/h82%96%2
Sun 3pRain55°13° (likely 51°11° to 59°15°)55°13°40%, 0.02 in0.5 mm3 mph5 km/h from ENE, gusts 5 mph9 km/h80%73%2
Sun 4pCloudy57°14° (likely 51°11° to 59°15°)57°14°50%, 0.02 in0.5 mm3 mph5 km/h from ENE, gusts 7 mph12 km/h79%94%1
Sun 5pCloudy55°13° (likely 52°11° to 57°14°)55°13°30%, 0.01 in0.3 mm2 mph3 km/h from N, gusts 10 mph16 km/h82%93%1
Sun 6pCloudy55°13° (likely 51°11° to 55°13°)55°13°30%, 0.01 in0.3 mm2 mph3 km/h from N, gusts 4 mph6 km/h83%88%0
Sun 7pCloudy54°12° (likely 50°10° to 54°12°)54°12°30%, 0.01 in0.3 mm2 mph3 km/h from N, gusts 3 mph5 km/h83%95%0
Sun 8pCloudy53°12° (likely 49°9° to 53°12°)53°12°30%, 0.01 in0.3 mm2 mph3 km/h from NE, gusts 3 mph6 km/h83%99%0
Sun 9pRain53°12° (likely 48°9° to 53°12°)53°12°30%, 0.01 in0.3 mm2 mph3 km/h from NE, gusts 3 mph5 km/h83%79%0
Sun 10pCloudy52°11° (likely 46°8° to 52°11°)52°11°30%, 0.01 in0.3 mm2 mph3 km/h from NE, gusts 4 mph7 km/h83%82%0
Sun 11pCloudy52°11° (likely 46°8° to 52°11°)52°11°30%2 mph3 km/h from NE, gusts 6 mph10 km/h84%88%0

Days ahead

Shaded: typical range for these dates (1991–2020)
  1. Today, Oct 24. Cloudy. High 56°13°, low 44°7°. Typical 58°14° / 45°7°. Dry. Mostly agree.
    1. Morning

      6 AM–noon

      Cloudy, 44°7°

      Dry

    2. Afternoon

      noon–6 PM

      Cloudy, 56°13°

      Dry

    3. Evening

      6 PM–midnight

      Cloudy, 52°11°

      Dry

    4. Overnight

      midnight–6 AM

      Mostly cloudy, 49°9°

      60% chance · 0.16 in4.1 mm

    Official NWS forecast

    Today: Partly sunny, with a high near 56. South southwest wind around 2 mph.

    Tonight: Mostly cloudy, with a low around 44. Southeast wind around 3 mph.

    Mostly agreeIndependent forecasts are fairly close; small surprises are possible.

    High, likely
    54°12°–59°15°
    Low, likely
    39°4°–44°7°
    Typical high / low
    58°14° / 45°7°
    Wind
    5 mph8 km/h
    UV peak
    2
  2. Tomorrow, Oct 25. Rain. High 57°14°, low 49°9°. Typical 57°14° / 45°7°. Rain 0.2 in5.1 mm, 60% chance. Forecasts differ.
    1. Morning

      6 AM–noon

      Rain, 49°9°

      60% chance · 0.32 in8.1 mm

    2. Afternoon

      noon–6 PM

      Rain, 57°14°

      60% chance · 0.11 in2.8 mm

    3. Evening

      6 PM–midnight

      Rain, 53°12°

      30% chance · 0.05 in1.3 mm

    4. Overnight

      midnight–6 AM

      Clear, 47°8°

      20% chance · 0.01 in0.3 mm

    Official NWS forecast

    Day: Rain likely. Cloudy, with a high near 57. Northeast wind around 3 mph. Chance of precipitation is 60%. New rainfall amounts less than a tenth of an inch possible.

    Night: A chance of rain. Mostly cloudy, with a low around 49. North northeast wind around 3 mph. Chance of precipitation is 30%. New rainfall amounts less than a tenth of an inch possible.

    Forecasts differIndependent forecasts disagree; expect changes and plan for the range.

    High, likely
    51°11°–57°14°
    Low, likely
    42°6°–49°9°
    Typical high / low
    57°14° / 45°7°
    Wind
    7 mph12 km/h, gusts 13 mph22 km/h
    UV peak
    2
  3. Monday, Oct 26. Rain. High 58°14°, low 49°9°. Typical 57°14° / 45°7°. Rain 0.06 in1.5 mm, 20% chance. Forecasts agree.
    1. Morning

      6 AM–noon

      Mostly sunny, 46°8°

      20% chance · 0.01 in0.4 mm

    2. Afternoon

      noon–6 PM

      Cloudy, 57°14°

      Dry

    3. Evening

      6 PM–midnight

      Partly cloudy, 50°10°

      Dry

    4. Overnight

      midnight–6 AM

      Drizzle, 48°9°

      30% chance · 0.03 in0.6 mm

    Hours this far out come from computer models only.

    Official NWS forecast

    Day: A slight chance of rain before 11am. Partly sunny, with a high near 58. Chance of precipitation is 20%.

    Night: A slight chance of rain after 11pm. Mostly cloudy, with a low around 49.

    Forecasts agreeIndependent forecasts are close; the range is narrow.

    High, likely
    55°13°–58°14°
    Low, likely
    43°6°–49°9°
    Typical high / low
    57°14° / 45°7°
    Wind
    7 mph11 km/h, gusts 16 mph25 km/h
    UV peak
    3
  4. Tuesday, Oct 27. Rain. High 58°14°, low 45°7°. Typical 57°14° / 45°7°. Rain 0.14 in3.6 mm, 20% chance. Mostly agree.
    1. Morning

      6 AM–noon

      Partly sunny, 49°9°

      30% chance · 0.03 in0.7 mm

    2. Afternoon

      noon–6 PM

      Drizzle, 55°13°

      30% chance · 0.03 in0.8 mm

    3. Evening

      6 PM–midnight

      Drizzle, 50°10°

      30% chance · 0.05 in1.1 mm

    4. Overnight

      midnight–6 AM

      Drizzle, 47°9°

      60% chance · 0.08 in1.9 mm

    Hours this far out come from computer models only.

    Official NWS forecast

    Day: A slight chance of rain. Mostly cloudy, with a high near 58.

    Night: A chance of rain. Mostly cloudy, with a low around 45.

    Mostly agreeIndependent forecasts are fairly close; small surprises are possible.

    High, likely
    53°12°–58°14°
    Low, likely
    45°7°–48°9°
    Typical high / low
    57°14° / 45°7°
    Wind
    15 mph23 km/h, gusts 28 mph45 km/h
  5. Wednesday, Oct 28. Rain. High 56°13°, low 42°6°. Typical 56°13° / 44°7°. Rain 0.3 in7.6 mm, 60% chance. Mostly agree.
    1. Morning

      6 AM–noon

      Drizzle, 47°9°

      50% chance · 0.09 in2.3 mm

    2. Afternoon

      noon–6 PM

      Drizzle, 52°11°

      60% chance · 0.07 in1.9 mm

    3. Evening

      6 PM–midnight

      Drizzle, 48°9°

      50% chance · 0.04 in1 mm

    4. Overnight

      midnight–6 AM

      Rain, 44°7°

      50% chance · 0.21 in5.3 mm

    Hours this far out come from computer models only.

    Official NWS forecast

    Day: Rain likely. Mostly cloudy, with a high near 56.

    Night: Rain likely. Mostly cloudy, with a low around 42.

    Mostly agreeIndependent forecasts are fairly close; small surprises are possible.

    High, likely
    50°10°–56°13°
    Low, likely
    42°6°–46°8°
    Typical high / low
    56°13° / 44°7°
    Wind
    13 mph21 km/h, gusts 28 mph45 km/h
    UV peak
    1
  6. Thursday, Oct 29. Rain. High 55°13°, low 41°5°. Typical 56°13° / 44°7°. Rain 0.44 in11 mm, 40% chance. Forecasts differ.
    1. Morning

      6 AM–noon

      Drizzle, 44°6°

      40% chance · 0.13 in3.4 mm

    2. Afternoon

      noon–6 PM

      Drizzle, 50°10°

      30% chance · 0.08 in1.9 mm

    3. Evening

      6 PM–midnight

      Drizzle, 46°8°

      Dry

    4. Overnight

      midnight–6 AM

      Cloudy, 44°7°

      Dry

    Hours this far out come from computer models only.

    Official NWS forecast

    Day: A chance of rain. Partly sunny, with a high near 55.

    Night: A slight chance of rain before 5am. Mostly cloudy, with a low around 41.

    Forecasts differIndependent forecasts disagree; expect changes and plan for the range.

    High, likely
    47°8°–55°13°
    Low, likely
    41°5°–44°7°
    Typical high / low
    56°13° / 44°7°
    Wind
    9 mph15 km/h, gusts 20 mph32 km/h
    UV peak
    1
  7. Friday, Oct 30. Drizzle. High 55°13°, low 41°5°. Typical 56°13° / 44°7°. Rain 0.11 in2.8 mm, 10% chance. Forecasts differ.
    1. Morning

      6 AM–noon

      Partly sunny, 44°7°

      Dry

    2. Afternoon

      noon–6 PM

      Cloudy, 50°10°

      Dry

    3. Evening

      6 PM–midnight

      Cloudy, 45°7°

      Dry

    4. Overnight

      midnight–6 AM

      Partly cloudy, 41°5°

      Dry

    Hours this far out come from computer models only.

    Official NWS forecast

    Day: Partly sunny, with a high near 55.

    Forecasts differIndependent forecasts disagree; expect changes and plan for the range.

    High, likely
    47°8°–55°13°
    Low, likely
    38°3°–45°7°
    Typical high / low
    56°13° / 44°7°
    Wind
    7 mph12 km/h, gusts 18 mph29 km/h
    UV peak
    3
  8. Saturday, Oct 31. Cloudy. High 49°9°, low 39°4°. Typical 56°13° / 44°7°. Dry. Mostly agree.
    1. Morning

      6 AM–noon

      Sunny, 40°5°

      Dry

    2. Afternoon

      noon–6 PM

      Sunny, 49°9°

      Dry

    3. Evening

      6 PM–midnight

      Clear, 43°6°

      Dry

    4. Overnight

      midnight–6 AM

      Clear, 40°4°

      Dry

    Hours this far out come from computer models only.

    The National Weather Service writes about seven days ahead; this day is our model forecast only.

    Mostly agreeIndependent forecasts are fairly close; small surprises are possible.

    High, likely
    46°8°–52°11°
    Low, likely
    38°3°–41°5°
    Typical high / low
    56°13° / 44°7°
    Wind
    7 mph11 km/h, gusts 15 mph23 km/h
    UV peak
    3
  9. Sunday, Nov 1. Sunny. High 52°11°, low 40°4°. Typical 55°13° / 44°7°. Dry. Mostly agree.
    1. Morning

      6 AM–noon

      Sunny, 41°5°

      Dry

    2. Afternoon

      noon–6 PM

      Sunny, 51°11°

      Dry

    3. Evening

      6 PM–midnight

      Clear, 47°8°

      Dry

    4. Overnight

      midnight–6 AM

      Mostly clear, 45°7°

      Dry

    Hours this far out come from computer models only.

    The National Weather Service writes about seven days ahead; this day is our model forecast only.

    Mostly agreeIndependent forecasts are fairly close; small surprises are possible.

    High, likely
    48°9°–54°12°
    Low, likely
    37°3°–44°7°
    Typical high / low
    55°13° / 44°7°
    Wind
    7 mph12 km/h, gusts 16 mph26 km/h
    UV peak
    3
  10. Monday, Nov 2. Partly sunny. High 54°12°, low 43°6°. Typical 55°13° / 43°6°. Rain 0.19 in4.8 mm, 20% chance. Mostly agree.
    1. Morning

      6 AM–noon

      Cloudy, 48°9°

      20% chance · 0.01 in0.3 mm

    2. Afternoon

      noon–6 PM

      Sunny, 55°13°

      20% chance · 0.06 in1.4 mm

    3. Evening

      6 PM–midnight

      Clear, 47°8°

      Dry

    Hours this far out come from computer models only.

    The National Weather Service writes about seven days ahead; this day is our model forecast only.

    Mostly agreeIndependent forecasts are fairly close; small surprises are possible.

    High, likely
    51°11°–57°14°
    Low, likely
    38°3°–46°8°
    Typical high / low
    55°13° / 43°6°
    Wind
    9 mph14 km/h
    UV peak
    3

The outlook

  1. Today

    Dry, high 56°, low 44°.

  2. Tomorrow

    58% chance of rain, high 57°, low 49°.

  3. Monday

    Dry, high 58°, low 49°.

  4. Rest of week

    Highs 49–58°; chance of precipitation on Wednesday.

Want the meteorologists’ reasoning? Read the NWS forecast discussion (SEW) (opens in a new tab)

What changed since yesterday

No meaningful changes from yesterday’s forecast.

Radar

Radar data: NOAA MRMS, rendered by forecast.blue
Radar loads when scrolled into view

Full-screen radar

Rivers

NOAA river gauges within 25 mi

Cedar River (WA) at Renton

5.8 mi
Below flood stage
Level
8.6 ft
Flow
323 cfs

Forecast peak 8.6 ft Sat 5 AM

Reading from Fri 10:15 PM · NWS gauge page

Snoqualmie River near Carnation

16 mi
Below flood stage
Level
44.4 ft
Flow
485 cfs

Forecast peak 44.7 ft Thu 5 AM

Reading from Fri 9:15 PM · NWS gauge page

Cedar River (WA) near Landsburg

18 mi
Below flood stage
Level
1.3 ft
Flow
359 cfs

Forecast peak 1.3 ft Sat 5 AM

Reading from Fri 11 PM · NWS gauge page

Duwamish River at Duwamish

5.1 mi
Level
0.2 ft

Reading from Fri 10:45 PM · NWS gauge page

For your home

What this week’s weather means for heating, cooling, pipes and fresh air.

Heating this week

About 71% less heating than a typical week.

This week 29Typical 101

Heating degree days, base 65°F

Heat-pump hours, next 7 days

h below 47°F
11
h below 17°F
0
h below 5°F
0

47, 17 and 5°F are the test points heat pumps are rated at.

Comfort

Dry air outside (dew point 37°F).

Open the windows?

No stretch in the next few days is comfortable enough outside, by temperature, dew point and air quality.

Is this typical?

Seattle Tacoma Area · official normals 1991–2020 · records 1945–2026

Oct 24, today vs a typical year

Today’s expected high is 2°1° colder than typical.

Normal high / low
58°14° / 45°7°
Forecast high / low
56°13° / 44°7°
Record high
72°22° in 1965
Record low
33°1° in 1954

Last 7 days vs normal

On average 1°0° warmer than normal (daily mean temperature).

  1. −1°SunOct 18
  2. +2°+1°MonOct 19
  3. +2°+1°TueOct 20
  4. +2°+1°WedOct 21
  5. +1°ThuOct 22
  6. —FriOct 23
  7. —SatOct 24

Mercer Island weather by month: normals, records, snow and freeze dates

Sun & moon

Sun

Sunrise 7:41 AM, sunset 6:04 PM.

Daylight
10 h 23 min
Losing 3 min 12 s a day; shortest Dec 21, 1 h 57 min less
Golden hour
5:20–6:23 PM
Morning 7:21–8:24 AM
Blue hour
6:23–6:35 PM
Morning 7:09–7:21 AM; first light 7:09 AM

Stars tonight? Poor

Clouds most of the night (about 62% cover).

Moon

Waxing gibbous

96% lit · growing

Today
sets 5:57 AM · rises 5:06 PM
Full moon
Oct 25
New moon
Nov 8
Looking southeast from Mercer Island. The highest point on the skyline is about 14,400 ft, 54 mi away.Skyline from USGS elevation data, heights drawn up to 6× taller. Sky, sun and moon as they are now.