Current Conditions

Mercer Island, Washington

59°F15°C

Partly Cloudy

Wind

SSE 3 mph6 km/h

Humidity

76%

Cloud Cover

74%

As of Tuesday, September 22, 2026 at 11:22 PM PDT

Today's Outlook

Night

Mostly cloudy, with a low around 53°F12°C. Light wind from the ESE around 5 mph7 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 in0.1 mm3%	Cloud 78%	Wind SSW 5 mph8 km/h	Wednesday: Overcast and mild, with a high of 66°F19°C and morning low of 54°F12°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 mph7 km/h.
Rain	High 61°F16°C	Low 50°F10°C	Precip 0.24 in6.2 mm95%	Cloud 96%	Wind N 4 mph6 km/h	Thursday: Overcast and mild, with a high of 61°F16°C and morning low of 52°F11°C. Light wind from the NNW around 4 mph7 km/h. 34% chance of drizzle in the afternoon. Dry air. Thursday Night: Overcast, with a low around 50°F10°C. Light wind from the NNE around 4 mph6 km/h. 95% chance of rain in the evening.
Rain	High 58°F15°C	Low 53°F11°C	Precip 0.65 in16.6 mm99%	Cloud 72%	Wind SSW 8 mph13 km/h	Friday: Overcast and mild, with a high of 58°F15°C. Breezy from the SSW at 11 to 12 mph17 to 19 km/h. 99% chance of rain throughout the day. Friday Night: Mostly cloudy, with a low around 53°F11°C. Breezy from the S at 6 to 8 mph10 to 13 km/h. 91% chance of showers throughout the night.
Drizzle	High 61°F16°C	Low 49°F9°CFeels 46°F8°C	Precip 0.02 in0.5 mm22%	Cloud 61%	Wind ENE 5 mph8 km/h	Saturday: Mostly cloudy and mild, with a high of 61°F16°C and morning low of 50°F10°C. Light wind from the NNE around 4 mph7 km/h. Dry air. Saturday Night: Mostly cloudy, with a low around 49°F9°C. Breezy from the ESE at 5 to 7 mph9 to 11 km/h. 22% chance of drizzle overnight.
Partly Cloudy	High 63°F17°C	Low 47°F9°C	Precip 0.01 in0.3 mm8%	Cloud 54%	Wind N 4 mph7 km/h	Sunday: Partly cloudy and mild, with a high of 63°F17°C and morning low of 50°F10°C. Light wind from the NNW around 5 mph8 km/h. Dry air. Sunday Night: Mostly cloudy, with a low around 47°F9°C. Light wind from the NNE around 4 mph6 km/h.
Drizzle	High 62°F17°C	Low 49°F9°C	Precip 0.09 in2.2 mm31%	Cloud 80%	Wind S 5 mph8 km/h	Monday: Overcast and mild, with a high of 62°F17°C and morning low of 50°F10°C. Light wind from the S around 5 mph8 km/h. 26% chance of drizzle throughout the day. Dry air. Monday Night: Mostly cloudy, with a low around 49°F9°C. Light wind from the SSE around 5 mph8 km/h. 31% chance of drizzle throughout the night.
Light Rain	High 63°F17°C	Low 54°F12°C	Precip 0.18 in4.5 mm42%	Cloud 78%	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 S at 7 mph11 km/h. 42% chance of light rain throughout the day. Tuesday Night: Mostly cloudy, with a low around 54°F12°C. Breezy from the S at 6 to 7 mph10 to 11 km/h. 40% 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 in0.1 mm· 3%	78%	Partly Cloudy	SSW 5 mph8 km/h
DayOvercast and mild, with a high of 66°F19°C and morning low of 54°F12°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 mph7 km/h.
	ThursdaySep 24	61°F16°C	50°F10°C	0.24 in6.2 mm· 95%	96%	Rain	N 4 mph6 km/h
DayOvercast and mild, with a high of 61°F16°C and morning low of 52°F11°C. Light wind from the NNW around 4 mph7 km/h. 34% chance of drizzle in the afternoon. Dry air. NightOvercast, with a low around 50°F10°C. Light wind from the NNE around 4 mph6 km/h. 95% chance of rain in the evening.
	FridaySep 25	58°F15°C	53°F11°C	0.65 in16.6 mm· 99%	72%	Rain	SSW 8 mph13 km/h
DayOvercast and mild, with a high of 58°F15°C. Breezy from the SSW at 11 to 12 mph17 to 19 km/h. 99% chance of rain throughout the day. NightMostly cloudy, with a low around 53°F11°C. Breezy from the S at 6 to 8 mph10 to 13 km/h. 91% chance of showers throughout the night.
	SaturdaySep 26	61°F16°C	49°F9°C Feels 46°F8°C	0.02 in0.5 mm· 22%	61%	Drizzle	ENE 5 mph8 km/h
DayMostly cloudy and mild, with a high of 61°F16°C and morning low of 50°F10°C. Light wind from the NNE around 4 mph7 km/h. Dry air. NightMostly cloudy, with a low around 49°F9°C. Breezy from the ESE at 5 to 7 mph9 to 11 km/h. 22% chance of drizzle overnight.
	SundaySep 27	63°F17°C	47°F9°C	0.01 in0.3 mm· 8%	54%	Partly Cloudy	N 4 mph7 km/h
DayPartly cloudy and mild, with a high of 63°F17°C and morning low of 50°F10°C. Light wind from the NNW around 5 mph8 km/h. Dry air. NightMostly cloudy, with a low around 47°F9°C. Light wind from the NNE around 4 mph6 km/h.
	MondaySep 28	62°F17°C	49°F9°C	0.09 in2.2 mm· 31%	80%	Drizzle	S 5 mph8 km/h
DayOvercast and mild, with a high of 62°F17°C and morning low of 50°F10°C. Light wind from the S around 5 mph8 km/h. 26% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 49°F9°C. Light wind from the SSE around 5 mph8 km/h. 31% chance of drizzle throughout the night.
	TuesdaySep 29	63°F17°C	54°F12°C	0.18 in4.5 mm· 42%	78%	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 S at 7 mph11 km/h. 42% chance of light rain throughout the day. NightMostly cloudy, with a low around 54°F12°C. Breezy from the S at 6 to 7 mph10 to 11 km/h. 40% chance of light rain throughout the night.
	WednesdaySep 30	64°F18°C	53°F11°C	0.12 in3.1 mm· 28%	71%	Drizzle	S 5 mph8 km/h
DayMostly cloudy and mild, with a high of 64°F18°C and morning low of 53°F12°C. Light wind from the SSW around 5 mph8 km/h. 28% chance of drizzle throughout the day. NightMostly cloudy, with a low around 53°F11°C. Light wind from the SSE around 5 mph8 km/h. 27% chance of drizzle throughout the night.
	ThursdayOct 1	62°F17°C	53°F12°C	0.15 in3.9 mm· 37%	66%	Showers	SSW 5 mph9 km/h
DayMostly cloudy and mild, with a high of 62°F17°C and morning low of 53°F12°C. Light wind from the SW around 6 mph9 km/h. 37% chance of showers throughout the day. Dry air. NightMostly cloudy, with a low around 53°F12°C. Light wind from the S around 5 mph8 km/h. 31% chance of showers throughout the night.
	FridayOct 2	62°F17°C	50°F10°C	0.07 in1.9 mm· 23%	55%	Drizzle	NNE 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 NNW around 5 mph8 km/h. 23% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 50°F10°C. Light wind from the E around 4 mph7 km/h. 21% chance of drizzle throughout the night.
	SaturdayOct 3	64°F18°C	49°F9°C	0.04 in1.1 mm· 11%	54%	Drizzle	NNE 5 mph7 km/h
DayMostly cloudy and mild, with a high of 64°F18°C and morning low of 49°F10°C. Light wind from the N around 5 mph8 km/h. 11% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 49°F9°C. Light wind from the NE around 4 mph7 km/h.
	SundayOct 4	65°F18°C	51°F11°C	0.08 in2 mm· 17%	55%	Drizzle	E 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 NW around 5 mph8 km/h. 17% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 51°F11°C. Light wind from the E around 5 mph7 km/h. 17% chance of drizzle throughout the night.
	MondayOct 5	66°F19°C	52°F11°C	0.08 in2.1 mm· 17%	52%	Drizzle	SSE 5 mph8 km/h
DayMostly cloudy and mild, with a high of 66°F19°C and morning low of 52°F11°C. Light wind from the SSW around 5 mph9 km/h. 15% chance of drizzle throughout the day. NightMostly cloudy, with a low around 52°F11°C. Light wind from the SE around 5 mph8 km/h. 17% chance of drizzle throughout the night.
	TuesdayOct 6	67°F19°C	53°F11°C	0.08 in2.1 mm· 16%	51%	Drizzle	SSE 5 mph9 km/h
DayMostly cloudy and mild, with a high of 67°F19°C and morning low of 54°F12°C. Light wind from the SW around 5 mph9 km/h. 16% 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. 16% chance of drizzle throughout the night.
	WednesdayOct 7	66°F19°C	53°F12°C	0.06 in1.5 mm· 19%	56%	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 mph8 km/h. 19% chance of drizzle throughout the day. NightMostly cloudy, with a low around 53°F12°C. Light wind from the SE around 5 mph8 km/h. 14% 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