Current Conditions

Castro Valley, California

50°F10°C

Clear

Wind

E 4 mph6 km/h

Humidity

84%

Cloud Cover

36%

As of Tuesday, October 13, 2026 at 5:36 AM PDT

Today's Outlook

Day

Mostly clear and warm, with a high of 73°F23°C and morning low of 50°F10°C. Breezy from the N at 7 to 8 mph11 to 13 km/h. Dry air.

Night

Mostly clear, with a low around 49°F9°C. Light wind from the WSW around 4 mph7 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Clear	High 73°F23°C	Low 49°F9°C	Precip 0 in0 mm—	Cloud 9%	Wind N 6 mph9 km/h	Tuesday: Mostly clear and warm, with a high of 73°F23°C and morning low of 50°F10°C. Breezy from the N at 7 to 8 mph11 to 13 km/h. Dry air. Tuesday Night: Mostly clear, with a low around 49°F9°C. Light wind from the WSW around 4 mph7 km/h.
Clear	High 76°F24°C	Low 49°F10°C	Precip 0 in0 mm—	Cloud 2%	Wind WSW 4 mph7 km/h	Wednesday: Mostly clear and warm, with a high of 76°F24°C and morning low of 50°F10°C. Light wind from the WNW around 4 mph6 km/h. Dry air. Wednesday Night: Mostly clear, with a low around 49°F10°C. Light wind from the SW around 4 mph7 km/h.
Clear	High 83°F28°C	Low 54°F12°C	Precip 0 in0 mm—	Cloud 2%	Wind ENE 5 mph8 km/h	Thursday: Mostly clear and warm, with a high of 83°F28°C and morning low of 55°F13°C. Light wind from the NE around 5 mph9 km/h. Dry air. Thursday Night: Mostly clear, with a low around 54°F12°C. Light wind from the SE around 4 mph7 km/h.
Clear	High 85°F30°C	Low 59°F15°C	Precip 0 in0 mm—	Cloud 0%	Wind ENE 5 mph8 km/h	Friday: Mostly clear and warm, with a high of 85°F30°C and morning low of 61°F16°C. Light wind from the NE around 5 mph8 km/h. Dry air. Friday Night: Mostly clear, with a low around 59°F15°C. Light wind from the S around 5 mph8 km/h.
Clear	High 79°F26°C	Low 59°F15°C	Precip 0 in0 mm—	Cloud 5%	Wind WSW 5 mph8 km/h	Saturday: Mostly clear and warm, with a high of 79°F26°C and morning low of 60°F15°C. Light wind from the WSW around 5 mph7 km/h. Dry air. Saturday Night: Mostly clear, with a low around 59°F15°C. Light wind from the SW around 5 mph8 km/h.
Clear	High 66°F19°C	Low 55°F13°C	Precip 0 in0 mm—	Cloud 32%	Wind SW 7 mph11 km/h	Sunday: Partly cloudy and mild, with a high of 66°F19°C and morning low of 55°F13°C. Breezy from the WSW at 7 to 9 mph11 to 14 km/h. Sunday Night: Partly cloudy, with a low around 55°F13°C. Breezy from the SW at 7 to 8 mph10 to 14 km/h.
Partly Cloudy	High 63°F17°C	Low 52°F11°C	Precip 0 in0 mm—	Cloud 54%	Wind WSW 8 mph12 km/h	Monday: Mostly cloudy and mild, with a high of 63°F17°C and morning low of 53°F12°C. Breezy from the WSW at 8 to 9 mph13 to 15 km/h. Dry air. Monday Night: Mostly cloudy, with a low around 52°F11°C. Breezy from the WSW at 7 to 9 mph12 to 14 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	TuesdayOct 13	73°F23°C	49°F9°C	0 in0 mm· —	9%	Clear	N 6 mph9 km/h
DayMostly clear and warm, with a high of 73°F23°C and morning low of 50°F10°C. Breezy from the N at 7 to 8 mph11 to 13 km/h. Dry air. NightMostly clear, with a low around 49°F9°C. Light wind from the WSW around 4 mph7 km/h.
	WednesdayOct 14	76°F24°C	49°F10°C	0 in0 mm· —	2%	Clear	WSW 4 mph7 km/h
DayMostly clear and warm, with a high of 76°F24°C and morning low of 50°F10°C. Light wind from the WNW around 4 mph6 km/h. Dry air. NightMostly clear, with a low around 49°F10°C. Light wind from the SW around 4 mph7 km/h.
	ThursdayOct 15	83°F28°C	54°F12°C	0 in0 mm· —	2%	Clear	ENE 5 mph8 km/h
DayMostly clear and warm, with a high of 83°F28°C and morning low of 55°F13°C. Light wind from the NE around 5 mph9 km/h. Dry air. NightMostly clear, with a low around 54°F12°C. Light wind from the SE around 4 mph7 km/h.
	FridayOct 16	85°F30°C	59°F15°C	0 in0 mm· —	0%	Clear	ENE 5 mph8 km/h
DayMostly clear and warm, with a high of 85°F30°C and morning low of 61°F16°C. Light wind from the NE around 5 mph8 km/h. Dry air. NightMostly clear, with a low around 59°F15°C. Light wind from the S around 5 mph8 km/h.
	SaturdayOct 17	79°F26°C	59°F15°C	0 in0 mm· —	5%	Clear	WSW 5 mph8 km/h
DayMostly clear and warm, with a high of 79°F26°C and morning low of 60°F15°C. Light wind from the WSW around 5 mph7 km/h. Dry air. NightMostly clear, with a low around 59°F15°C. Light wind from the SW around 5 mph8 km/h.
	SundayOct 18	66°F19°C	55°F13°C	0 in0 mm· —	32%	Clear	SW 7 mph11 km/h
DayPartly cloudy and mild, with a high of 66°F19°C and morning low of 55°F13°C. Breezy from the WSW at 7 to 9 mph11 to 14 km/h. NightPartly cloudy, with a low around 55°F13°C. Breezy from the SW at 7 to 8 mph10 to 14 km/h.
	MondayOct 19	63°F17°C	52°F11°C	0 in0 mm· —	54%	Partly Cloudy	WSW 8 mph12 km/h
DayMostly cloudy and mild, with a high of 63°F17°C and morning low of 53°F12°C. Breezy from the WSW at 8 to 9 mph13 to 15 km/h. Dry air. NightMostly cloudy, with a low around 52°F11°C. Breezy from the WSW at 7 to 9 mph12 to 14 km/h.
	TuesdayOct 20	65°F18°C	53°F12°C	0.02 in0.5 mm· 9%	38%	Clear	W 7 mph11 km/h
DayPartly cloudy and mild, with a high of 65°F18°C and morning low of 54°F12°C. Breezy from the W at 7 to 8 mph11 to 13 km/h. Dry air. NightPartly cloudy, with a low around 53°F12°C. Breezy from the WSW at 7 to 8 mph11 to 12 km/h.
	WednesdayOct 21	68°F20°C	53°F12°C	0.02 in0.4 mm· 6%	20%	Clear	WNW 6 mph10 km/h
DayMostly clear and warm, with a high of 68°F20°C and morning low of 54°F12°C. Breezy from the NNW at 6 to 7 mph10 to 11 km/h. Dry air. NightMostly clear, with a low around 53°F12°C. Light wind from the W around 6 mph9 km/h.
	ThursdayOct 22	68°F20°C	52°F11°C	0.01 in0.3 mm· 3%	20%	Clear	SW 5 mph8 km/h
DayMostly clear and warm, with a high of 68°F20°C and morning low of 53°F12°C. Light wind from the WSW around 5 mph8 km/h. Dry air. NightMostly clear, with a low around 52°F11°C. Light wind from the SW around 5 mph8 km/h.
	FridayOct 23	68°F20°C	52°F11°C	0.01 in0.2 mm· 3%	31%	Clear	SW 5 mph8 km/h
DayPartly cloudy and mild, with a high of 68°F20°C and morning low of 53°F12°C. Light wind from the WSW around 5 mph8 km/h. Dry air. NightPartly cloudy, with a low around 52°F11°C. Light wind from the SW around 5 mph8 km/h.
	SaturdayOct 24	70°F21°C	53°F11°C	0 in0.1 mm· 1%	31%	Clear	WSW 5 mph8 km/h
DayPartly cloudy and warm, with a high of 70°F21°C and morning low of 53°F12°C. Light wind from the W around 5 mph8 km/h. Dry air. NightPartly cloudy, with a low around 53°F11°C. Light wind from the SW around 5 mph8 km/h.
	SundayOct 25	71°F22°C	53°F12°C	0.02 in0.4 mm· 4%	32%	Clear	SW 5 mph8 km/h
DayPartly cloudy and warm, with a high of 71°F22°C and morning low of 54°F12°C. Light wind from the NNE around 5 mph8 km/h. Dry air. NightPartly cloudy, with a low around 53°F12°C. Light wind from the SW around 5 mph7 km/h.
	MondayOct 26	71°F21°C	53°F12°C	0.02 in0.4 mm· 2%	28%	Clear	SW 5 mph8 km/h
DayPartly cloudy and warm, with a high of 71°F21°C and morning low of 54°F12°C. Light wind from the WSW around 5 mph8 km/h. Dry air. NightPartly cloudy, with a low around 53°F12°C. Light wind from the SW around 5 mph8 km/h.
	TuesdayOct 27	70°F21°C	53°F12°C	0.01 in0.2 mm· 2%	34%	Clear	WSW 5 mph8 km/h
DayPartly cloudy and warm, with a high of 70°F21°C and morning low of 54°F12°C. Light wind from the WSW around 5 mph8 km/h. Dry air. NightPartly cloudy, with a low around 53°F12°C. Light wind from the WSW around 5 mph8 km/h.

Nearby Cities

Ashland2 mi2 km Hayward2 mi3 km San Lorenzo3 mi5 km San Leandro4 mi7 km Union City8 mi12 km Dublin8 mi13 km

About This Forecast

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Coordinates: 37.6941°N, 122.0863°W·Elevation: 50m·Timezone: America/Los_Angeles·Population: 61,388