Current Conditions

Castro Valley, California

66°F19°C

Partly Cloudy

Wind

SSW 10 mph15 km/h

Humidity

68%

Cloud Cover

82%

As of Thursday, August 13, 2026 at 11:08 AM PDT

Today's Outlook

Day

Mostly cloudy and warm, with a high of 70°F21°C and morning low of 61°F16°C. Breezy from the SW at 10 to 11 mph16 to 18 km/h.

Night

Overcast, with a low around 59°F15°C. Breezy from the SW at 8 to 9 mph13 to 14 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Partly Cloudy	High 70°F21°C	Low 59°F15°C	Precip 0 in0 mm—	Cloud 79%	Wind SW 9 mph15 km/h	Thursday: Mostly cloudy and warm, with a high of 70°F21°C and morning low of 61°F16°C. Breezy from the SW at 10 to 11 mph16 to 18 km/h. Thursday Night: Overcast, with a low around 59°F15°C. Breezy from the SW at 8 to 9 mph13 to 14 km/h.
Partly Cloudy	High 70°F21°C	Low 58°F15°C	Precip 0 in0.1 mm—	Cloud 68%	Wind WSW 7 mph11 km/h	Friday: Mostly cloudy and warm, with a high of 70°F21°C and morning low of 60°F16°C. Breezy from the WSW at 8 to 9 mph12 to 15 km/h. Friday Night: Mostly cloudy, with a low around 58°F15°C. Breezy from the WSW at 6 to 7 mph10 to 12 km/h.
Partly Cloudy	High 72°F22°C	Low 58°F14°C	Precip 0 in0 mm—	Cloud 63%	Wind WSW 6 mph9 km/h	Saturday: Mostly cloudy and warm, with a high of 72°F22°C and morning low of 59°F15°C. Breezy from the WSW at 6 to 9 mph10 to 14 km/h. Saturday Night: Mostly cloudy, with a low around 58°F14°C. Light wind from the WSW around 5 mph8 km/h.
Partly Cloudy	High 75°F24°C	Low 57°F14°C	Precip 0 in0 mm—	Cloud 79%	Wind WSW 5 mph8 km/h	Sunday: Mostly cloudy and warm, with a high of 75°F24°C and morning low of 59°F15°C. Breezy from the W at 6 to 8 mph9 to 13 km/h. Sunday Night: Mostly cloudy, with a low around 57°F14°C. Light wind from the WSW around 5 mph7 km/h.
Cloudy	High 74°F23°C	Low 58°F14°C	Precip 0 in0 mm—	Cloud 80%	Wind WSW 6 mph10 km/h	Monday: Mostly cloudy and warm, with a high of 74°F23°C and morning low of 59°F15°C. Breezy from the WSW at 7 to 9 mph11 to 14 km/h. Monday Night: Overcast, with a low around 58°F14°C. Light wind from the WSW around 5 mph8 km/h.
Partly Cloudy	High 76°F24°C	Low 58°F14°C	Precip 0 in0 mm—	Cloud 59%	Wind WSW 6 mph9 km/h	Tuesday: Mostly cloudy and warm, with a high of 76°F24°C and morning low of 60°F15°C. Breezy from the WSW at 6 to 8 mph10 to 13 km/h. Tuesday Night: Mostly cloudy, with a low around 58°F14°C. Light wind from the SW around 5 mph8 km/h.
Partly Cloudy	High 74°F24°C	Low 58°F14°C	Precip 0 in0 mm—	Cloud 52%	Wind WSW 6 mph10 km/h	Wednesday: Partly cloudy and warm, with a high of 74°F24°C and morning low of 60°F15°C. Breezy from the WSW at 7 to 9 mph12 to 14 km/h. Wednesday Night: Mostly cloudy, with a low around 58°F14°C. Breezy from the SW at 6 to 7 mph9 to 11 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	ThursdayAug 13	70°F21°C	59°F15°C	0 in0 mm· —	79%	Partly Cloudy	SW 9 mph15 km/h
DayMostly cloudy and warm, with a high of 70°F21°C and morning low of 61°F16°C. Breezy from the SW at 10 to 11 mph16 to 18 km/h. NightOvercast, with a low around 59°F15°C. Breezy from the SW at 8 to 9 mph13 to 14 km/h.
	FridayAug 14	70°F21°C	58°F15°C	0 in0.1 mm· —	68%	Partly Cloudy	WSW 7 mph11 km/h
DayMostly cloudy and warm, with a high of 70°F21°C and morning low of 60°F16°C. Breezy from the WSW at 8 to 9 mph12 to 15 km/h. NightMostly cloudy, with a low around 58°F15°C. Breezy from the WSW at 6 to 7 mph10 to 12 km/h.
	SaturdayAug 15	72°F22°C	58°F14°C	0 in0 mm· —	63%	Partly Cloudy	WSW 6 mph9 km/h
DayMostly cloudy and warm, with a high of 72°F22°C and morning low of 59°F15°C. Breezy from the WSW at 6 to 9 mph10 to 14 km/h. NightMostly cloudy, with a low around 58°F14°C. Light wind from the WSW around 5 mph8 km/h.
	SundayAug 16	75°F24°C	57°F14°C	0 in0 mm· —	79%	Partly Cloudy	WSW 5 mph8 km/h
DayMostly cloudy and warm, with a high of 75°F24°C and morning low of 59°F15°C. Breezy from the W at 6 to 8 mph9 to 13 km/h. NightMostly cloudy, with a low around 57°F14°C. Light wind from the WSW around 5 mph7 km/h.
	MondayAug 17	74°F23°C	58°F14°C	0 in0 mm· —	80%	Cloudy	WSW 6 mph10 km/h
DayMostly cloudy and warm, with a high of 74°F23°C and morning low of 59°F15°C. Breezy from the WSW at 7 to 9 mph11 to 14 km/h. NightOvercast, with a low around 58°F14°C. Light wind from the WSW around 5 mph8 km/h.
	TuesdayAug 18	76°F24°C	58°F14°C	0 in0 mm· —	59%	Partly Cloudy	WSW 6 mph9 km/h
DayMostly cloudy and warm, with a high of 76°F24°C and morning low of 60°F15°C. Breezy from the WSW at 6 to 8 mph10 to 13 km/h. NightMostly cloudy, with a low around 58°F14°C. Light wind from the SW around 5 mph8 km/h.
	WednesdayAug 19	74°F24°C	58°F14°C	0 in0 mm· —	52%	Partly Cloudy	WSW 6 mph10 km/h
DayPartly cloudy and warm, with a high of 74°F24°C and morning low of 60°F15°C. Breezy from the WSW at 7 to 9 mph12 to 14 km/h. NightMostly cloudy, with a low around 58°F14°C. Breezy from the SW at 6 to 7 mph9 to 11 km/h.
	ThursdayAug 20	74°F23°C	57°F14°C	0 in0 mm· —	56%	Partly Cloudy	WSW 6 mph10 km/h
DayMostly cloudy and warm, with a high of 74°F23°C and morning low of 60°F15°C. Breezy from the WSW at 7 to 9 mph12 to 14 km/h. NightMostly cloudy, with a low around 57°F14°C. Light wind from the SW around 6 mph9 km/h.
	FridayAug 21	74°F24°C	58°F14°C	0 in0 mm· —	50%	Partly Cloudy	WSW 6 mph10 km/h
DayPartly cloudy and warm, with a high of 74°F24°C and morning low of 60°F15°C. Breezy from the WSW at 7 to 9 mph11 to 14 km/h. NightMostly cloudy, with a low around 58°F14°C. Light wind from the WSW around 5 mph9 km/h.
	SaturdayAug 22	77°F25°C	58°F14°C	0 in0 mm· —	38%	Clear	WSW 6 mph9 km/h
DayPartly cloudy and warm, with a high of 77°F25°C and morning low of 61°F16°C. Breezy from the WSW at 6 to 8 mph10 to 14 km/h. NightPartly cloudy, with a low around 58°F14°C. Light wind from the SW around 5 mph8 km/h.
	SundayAug 23	78°F26°C	58°F14°C	0 in0 mm· —	29%	Clear	WSW 5 mph9 km/h
DayPartly cloudy and warm, with a high of 78°F26°C and morning low of 61°F16°C. Breezy from the WSW at 6 to 8 mph10 to 13 km/h. NightPartly cloudy, with a low around 58°F14°C. Light wind from the SW around 5 mph7 km/h.
	MondayAug 24	79°F26°C	58°F15°C	0 in0 mm· —	27%	Clear	WSW 5 mph9 km/h
DayMostly clear and warm, with a high of 79°F26°C and morning low of 62°F16°C. Breezy from the WSW at 6 to 8 mph10 to 13 km/h. NightPartly cloudy, with a low around 58°F15°C. Light wind from the SW around 5 mph7 km/h.
	TuesdayAug 25	77°F25°C	58°F15°C	0 in0 mm· —	31%	Clear	WSW 6 mph9 km/h
DayPartly cloudy and warm, with a high of 77°F25°C and morning low of 62°F17°C. Breezy from the WSW at 6 to 8 mph10 to 14 km/h. NightPartly cloudy, with a low around 58°F15°C. Light wind from the SW around 5 mph8 km/h.
	WednesdayAug 26	77°F25°C	57°F14°C	0 in0 mm· —	36%	Clear	WSW 5 mph9 km/h
DayPartly cloudy and warm, with a high of 77°F25°C and morning low of 60°F16°C. Breezy from the WSW at 6 to 8 mph10 to 13 km/h. NightPartly cloudy, with a low around 57°F14°C. Light wind from the SW around 5 mph7 km/h.
	ThursdayAug 27	77°F25°C	57°F14°C	0.01 in0.3 mm· 3%	41%	Partly Cloudy	WSW 5 mph9 km/h
DayPartly cloudy and warm, with a high of 77°F25°C and morning low of 60°F15°C. Breezy from the WSW at 6 to 8 mph10 to 13 km/h. NightPartly cloudy, with a low around 57°F14°C. Light wind from the SW around 5 mph7 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