Current Conditions

Mercer Island, Washington

62°F17°C

Partly Cloudy

Wind

ESE 3 mph5 km/h

Humidity

71%

Cloud Cover

75%

As of Tuesday, September 22, 2026 at 7:37 PM PDT

Today's Outlook

Night

Mostly cloudy, with a low around 53°F12°C. Light wind from the ESE around 5 mph8 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Partly Cloudy	High 66°F19°C	Low 53°F12°C	Precip 0.01 in0.2 mm9%	Cloud 80%	Wind S 5 mph8 km/h	Wednesday: Overcast and mild, with a high of 66°F19°C and morning low of 55°F13°C. Light wind from the SSW around 5 mph8 km/h. Dry air. Wednesday Night: Mostly cloudy, with a low around 53°F12°C. Light wind from the ESE around 5 mph8 km/h.
Rain	High 60°F15°C	Low 51°F11°C	Precip 0.2 in5 mm98%	Cloud 98%	Wind N 4 mph7 km/h	Thursday: Overcast and mild, with a high of 60°F15°C and morning low of 52°F11°C. Light wind from the NNW around 5 mph7 km/h. 46% chance of light rain in the afternoon. Dry air. Thursday Night: Overcast, with a low around 51°F11°C. Light wind from the NNE around 4 mph6 km/h. 98% chance of rain in the evening.
Rain	High 59°F15°C	Low 52°F11°C	Precip 0.64 in16.2 mm97%	Cloud 74%	Wind SSW 7 mph11 km/h	Friday: Overcast and mild, with a high of 59°F15°C and morning low of 54°F12°C. Breezy from the SSW at 8 to 9 mph14 to 15 km/h. 97% chance of rain throughout the day. Friday Night: Mostly cloudy, with a low around 52°F11°C. Light wind from the S around 5 mph9 km/h. 94% chance of showers throughout the night.
Drizzle	High 61°F16°C	Low 48°F9°C	Precip 0.01 in0.3 mm17%	Cloud 64%	Wind NNE 5 mph8 km/h	Saturday: Mostly cloudy and mild, with a high of 61°F16°C and morning low of 49°F9°C. Light wind from the N around 5 mph8 km/h. Dry air. Saturday Night: Mostly cloudy, with a low around 48°F9°C. Light wind from the E around 5 mph8 km/h. 17% chance of drizzle overnight.
Drizzle	High 63°F17°C	Low 48°F9°C	Precip 0.02 in0.6 mm12%	Cloud 50%	Wind N 4 mph7 km/h	Sunday: Partly cloudy and mild, with a high of 63°F17°C and morning low of 51°F10°C. Light wind from the NNW around 5 mph8 km/h. 12% chance of drizzle in the afternoon. Dry air. Sunday Night: Mostly cloudy, with a low around 48°F9°C. Light wind from the NE around 4 mph6 km/h.
Light Rain	High 63°F17°C	Low 49°F10°C	Precip 0.09 in2.4 mm30%	Cloud 81%	Wind S 5 mph8 km/h	Monday: Overcast and mild, with a high of 63°F17°C and morning low of 50°F10°C. Light wind from the S around 5 mph8 km/h. 28% chance of drizzle throughout the day. Dry air. Monday Night: Mostly cloudy, with a low around 49°F10°C. Light wind from the SSE around 5 mph8 km/h. 30% chance of light rain throughout the night.
Light Rain	High 63°F17°C	Low 54°F12°C	Precip 0.24 in6.1 mm43%	Cloud 80%	Wind S 6 mph10 km/h	Tuesday: Overcast and mild, with a high of 63°F17°C and morning low of 55°F13°C. Breezy from the SSW at 6 to 7 mph10 to 11 km/h. 43% chance of light rain throughout the day. Tuesday Night: Mostly cloudy, with a low around 54°F12°C. Light wind from the S around 6 mph10 km/h. 37% chance of light rain throughout the night.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	WednesdaySep 23	66°F19°C	53°F12°C	0.01 in0.2 mm· 9%	80%	Partly Cloudy	S 5 mph8 km/h
DayOvercast and mild, with a high of 66°F19°C and morning low of 55°F13°C. Light wind from the SSW around 5 mph8 km/h. Dry air. NightMostly cloudy, with a low around 53°F12°C. Light wind from the ESE around 5 mph8 km/h.
	ThursdaySep 24	60°F15°C	51°F11°C	0.2 in5 mm· 98%	98%	Rain	N 4 mph7 km/h
DayOvercast and mild, with a high of 60°F15°C and morning low of 52°F11°C. Light wind from the NNW around 5 mph7 km/h. 46% chance of light rain in the afternoon. Dry air. NightOvercast, with a low around 51°F11°C. Light wind from the NNE around 4 mph6 km/h. 98% chance of rain in the evening.
	FridaySep 25	59°F15°C	52°F11°C	0.64 in16.2 mm· 97%	74%	Rain	SSW 7 mph11 km/h
DayOvercast and mild, with a high of 59°F15°C and morning low of 54°F12°C. Breezy from the SSW at 8 to 9 mph14 to 15 km/h. 97% chance of rain throughout the day. NightMostly cloudy, with a low around 52°F11°C. Light wind from the S around 5 mph9 km/h. 94% chance of showers throughout the night.
	SaturdaySep 26	61°F16°C	48°F9°C	0.01 in0.3 mm· 17%	64%	Drizzle	NNE 5 mph8 km/h
DayMostly cloudy and mild, with a high of 61°F16°C and morning low of 49°F9°C. Light wind from the N around 5 mph8 km/h. Dry air. NightMostly cloudy, with a low around 48°F9°C. Light wind from the E around 5 mph8 km/h. 17% chance of drizzle overnight.
	SundaySep 27	63°F17°C	48°F9°C	0.02 in0.6 mm· 12%	50%	Drizzle	N 4 mph7 km/h
DayPartly cloudy and mild, with a high of 63°F17°C and morning low of 51°F10°C. Light wind from the NNW around 5 mph8 km/h. 12% chance of drizzle in the afternoon. Dry air. NightMostly cloudy, with a low around 48°F9°C. Light wind from the NE around 4 mph6 km/h.
	MondaySep 28	63°F17°C	49°F10°C	0.09 in2.4 mm· 30%	81%	Light Rain	S 5 mph8 km/h
DayOvercast and mild, with a high of 63°F17°C and morning low of 50°F10°C. Light wind from the S around 5 mph8 km/h. 28% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 49°F10°C. Light wind from the SSE around 5 mph8 km/h. 30% chance of light rain throughout the night.
	TuesdaySep 29	63°F17°C	54°F12°C	0.24 in6.1 mm· 43%	80%	Light Rain	S 6 mph10 km/h
DayOvercast and mild, with a high of 63°F17°C and morning low of 55°F13°C. Breezy from the SSW at 6 to 7 mph10 to 11 km/h. 43% chance of light rain throughout the day. NightMostly cloudy, with a low around 54°F12°C. Light wind from the S around 6 mph10 km/h. 37% chance of light rain throughout the night.
	WednesdaySep 30	63°F17°C	54°F12°C	0.17 in4.4 mm· 42%	72%	Light Rain	S 6 mph9 km/h
DayMostly cloudy and mild, with a high of 63°F17°C and morning low of 54°F12°C. Light wind from the SSW around 6 mph9 km/h. 42% chance of light rain throughout the day. NightMostly cloudy, with a low around 54°F12°C. Light wind from the S around 6 mph9 km/h. 37% chance of light rain throughout the night.
	ThursdayOct 1	62°F16°C	52°F11°C	0.19 in4.7 mm· 43%	68%	Showers	S 6 mph9 km/h
DayMostly cloudy and mild, with a high of 62°F16°C and morning low of 54°F12°C. Light wind from the SSW around 6 mph10 km/h. 43% chance of showers throughout the day. Dry air. NightMostly cloudy, with a low around 52°F11°C. Light wind from the SSE around 5 mph9 km/h. 35% chance of showers throughout the night.
	FridayOct 2	62°F17°C	50°F10°C	0.11 in2.7 mm· 27%	59%	Showers	SSE 5 mph8 km/h
DayMostly cloudy and mild, with a high of 62°F17°C and morning low of 51°F11°C. Light wind from the W around 5 mph8 km/h. 27% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 50°F10°C. Light wind from the SE around 5 mph8 km/h. 27% chance of showers throughout the night.
	SaturdayOct 3	64°F18°C	49°F10°C	0.07 in1.8 mm· 16%	55%	Drizzle	ENE 5 mph8 km/h
DayMostly cloudy and mild, with a high of 64°F18°C and morning low of 50°F10°C. Light wind from the N around 5 mph8 km/h. 16% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 49°F10°C. Light wind from the E around 5 mph7 km/h. 13% chance of drizzle throughout the night.
	SundayOct 4	65°F18°C	51°F11°C	0.08 in2.1 mm· 18%	59%	Drizzle	SSE 5 mph8 km/h
DayMostly cloudy and mild, with a high of 65°F18°C and morning low of 52°F11°C. Light wind from the SW around 5 mph8 km/h. 18% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 51°F11°C. Light wind from the SE around 5 mph8 km/h. 16% chance of drizzle throughout the night.
	MondayOct 5	66°F19°C	52°F11°C	0.09 in2.4 mm· 23%	53%	Drizzle	S 6 mph9 km/h
DayMostly cloudy and mild, with a high of 66°F19°C and morning low of 53°F12°C. Light wind from the SSW around 6 mph9 km/h. 23% chance of drizzle throughout the day. NightMostly cloudy, with a low around 52°F11°C. Light wind from the SSE around 5 mph9 km/h. 17% chance of drizzle throughout the night.
	TuesdayOct 6	66°F19°C	53°F11°C	0.11 in2.9 mm· 21%	51%	Drizzle	SSE 5 mph9 km/h
DayMostly cloudy and mild, with a high of 66°F19°C and morning low of 53°F12°C. Light wind from the SSW around 6 mph9 km/h. 21% chance of drizzle throughout the day. NightMostly cloudy, with a low around 53°F11°C. Light wind from the SE around 5 mph8 km/h. 18% chance of drizzle throughout the night.
	WednesdayOct 7	66°F19°C	53°F12°C	0.09 in2.3 mm· 23%	57%	Drizzle	S 5 mph8 km/h
DayMostly cloudy and mild, with a high of 66°F19°C and morning low of 53°F12°C. Light wind from the SSW around 5 mph9 km/h. 23% chance of drizzle throughout the day. NightMostly cloudy, with a low around 53°F12°C. Light wind from the SSE around 5 mph8 km/h. 21% chance of drizzle throughout the night.

Nearby Cities

Columbia City3 mi4 km Bellevue3 mi5 km Bryn Mawr-Skyway5 mi9 km West Lake Sammamish6 mi9 km Seattle6 mi9 km Renton6 mi10 km

About This Forecast

This forecast is powered by WeatherMesh, the world's most advanced and accurate weather model powered by AI. WeatherMesh is built on proprietary data from WindBorne's Global Sounding Balloon constellation — the world's largest fleet of autonomous, long-duration weather balloons — collecting observations across 100% of Earth, including over oceans and remote regions where no other data exists.

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Coordinates: 47.5707°N, 122.2221°W·Elevation: 102m·Timezone: America/Los_Angeles·Population: 25,042