Current Conditions

Castro Valley, California

72°F22°C

Partly Cloudy

Wind

WSW 10 mph15 km/h

Humidity

56%

Cloud Cover

68%

As of Wednesday, August 12, 2026 at 5:11 PM PDT

Today's Outlook

Day

Mostly cloudy and warm, with a high of 76°F24°C and morning low of 69°F21°C. Breezy from the SW at 8 to 10 mph13 to 15 km/h.

Night

Overcast, with a low around 62°F17°C. Breezy from the SW at 8 mph13 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Partly Cloudy	High 76°F24°C	Low 62°F17°C	Precip 0 in0 mm—	Cloud 72%	Wind SW 8 mph13 km/h	Wednesday: Mostly cloudy and warm, with a high of 76°F24°C and morning low of 69°F21°C. Breezy from the SW at 8 to 10 mph13 to 15 km/h. Wednesday Night: Overcast, with a low around 62°F17°C. Breezy from the SW at 8 mph13 km/h.
Partly Cloudy	High 70°F21°C	Low 59°F15°C	Precip 0 in0.1 mm—	Cloud 75%	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 17 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 75%	Wind WSW 7 mph12 km/h	Friday: Mostly cloudy and warm, with a high of 70°F21°C and morning low of 60°F16°C. Breezy from the SW at 8 to 10 mph13 to 15 km/h. Friday Night: Overcast, with a low around 58°F15°C. Breezy from the WSW at 7 to 8 mph11 to 12 km/h.
Partly Cloudy	High 72°F22°C	Low 57°F14°C	Precip 0 in0 mm—	Cloud 68%	Wind WSW 6 mph10 km/h	Saturday: Mostly cloudy and warm, with a high of 72°F22°C and morning low of 60°F15°C. Breezy from the WSW at 7 to 9 mph11 to 14 km/h. Saturday Night: Mostly cloudy, with a low around 57°F14°C. Light wind from the WSW around 5 mph9 km/h.
Cloudy	High 74°F23°C	Low 56°F14°C	Precip 0 in0 mm—	Cloud 82%	Wind WSW 5 mph9 km/h	Sunday: Mostly cloudy and warm, with a high of 74°F23°C and morning low of 58°F15°C. Breezy from the W at 6 to 8 mph10 to 13 km/h. Sunday Night: Overcast, with a low around 56°F14°C. Light wind from the WSW around 5 mph8 km/h.
Cloudy	High 73°F23°C	Low 57°F14°C	Precip 0 in0 mm—	Cloud 85%	Wind WSW 6 mph9 km/h	Monday: Overcast and warm, with a high of 73°F23°C and morning low of 60°F15°C. Breezy from the WSW at 6 to 8 mph10 to 13 km/h. Monday Night: Overcast, with a low around 57°F14°C. Light wind from the WSW around 5 mph8 km/h.
Partly Cloudy	High 74°F23°C	Low 58°F14°C	Precip 0 in0 mm—	Cloud 62%	Wind WSW 6 mph10 km/h	Tuesday: Mostly cloudy and warm, with a high of 74°F23°C and morning low of 60°F15°C. Breezy from the WSW at 7 to 8 mph11 to 14 km/h. Tuesday Night: Mostly cloudy, with a low around 58°F14°C. Light wind from the SW around 5 mph8 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	WednesdayAug 12	76°F24°C	62°F17°C	0 in0 mm· —	72%	Partly Cloudy	SW 8 mph13 km/h
DayMostly cloudy and warm, with a high of 76°F24°C and morning low of 69°F21°C. Breezy from the SW at 8 to 10 mph13 to 15 km/h. NightOvercast, with a low around 62°F17°C. Breezy from the SW at 8 mph13 km/h.
	ThursdayAug 13	70°F21°C	59°F15°C	0 in0.1 mm· —	75%	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 17 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· —	75%	Partly Cloudy	WSW 7 mph12 km/h
DayMostly cloudy and warm, with a high of 70°F21°C and morning low of 60°F16°C. Breezy from the SW at 8 to 10 mph13 to 15 km/h. NightOvercast, with a low around 58°F15°C. Breezy from the WSW at 7 to 8 mph11 to 12 km/h.
	SaturdayAug 15	72°F22°C	57°F14°C	0 in0 mm· —	68%	Partly Cloudy	WSW 6 mph10 km/h
DayMostly cloudy and warm, with a high of 72°F22°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 57°F14°C. Light wind from the WSW around 5 mph9 km/h.
	SundayAug 16	74°F23°C	56°F14°C	0 in0 mm· —	82%	Cloudy	WSW 5 mph9 km/h
DayMostly cloudy and warm, with a high of 74°F23°C and morning low of 58°F15°C. Breezy from the W at 6 to 8 mph10 to 13 km/h. NightOvercast, with a low around 56°F14°C. Light wind from the WSW around 5 mph8 km/h.
	MondayAug 17	73°F23°C	57°F14°C	0 in0 mm· —	85%	Cloudy	WSW 6 mph9 km/h
DayOvercast and warm, with a high of 73°F23°C and morning low of 60°F15°C. Breezy from the WSW at 6 to 8 mph10 to 13 km/h. NightOvercast, with a low around 57°F14°C. Light wind from the WSW around 5 mph8 km/h.
	TuesdayAug 18	74°F23°C	58°F14°C	0 in0 mm· —	62%	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 8 mph11 to 14 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	57°F14°C	0 in0.1 mm· 2%	48%	Partly Cloudy	WSW 6 mph10 km/h
DayPartly cloudy and warm, with a high of 74°F24°C and morning low of 60°F16°C. Breezy from the WSW at 7 to 9 mph11 to 14 km/h. NightMostly cloudy, with a low around 57°F14°C. Light wind from the SW around 5 mph9 km/h.
	ThursdayAug 20	75°F24°C	58°F14°C	0 in0 mm· —	40%	Partly Cloudy	WSW 6 mph10 km/h
DayPartly cloudy and warm, with a high of 75°F24°C and morning low of 60°F16°C. Breezy from the WSW at 7 to 8 mph11 to 14 km/h. NightPartly cloudy, with a low around 58°F14°C. Light wind from the SW around 5 mph8 km/h.
	FridayAug 21	77°F25°C	58°F14°C	0 in0 mm· —	37%	Clear	WSW 5 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 13 km/h. NightPartly cloudy, with a low around 58°F14°C. Light wind from the SW around 5 mph8 km/h.
	SaturdayAug 22	78°F25°C	58°F15°C	0 in0 mm· —	36%	Clear	WSW 5 mph9 km/h
DayPartly cloudy and warm, with a high of 78°F25°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°F15°C. Light wind from the SW around 5 mph7 km/h.
	SundayAug 23	77°F25°C	59°F15°C	0 in0 mm· —	35%	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 13 km/h. NightPartly cloudy, with a low around 59°F15°C. Light wind from the SW around 5 mph8 km/h.
	MondayAug 24	76°F25°C	59°F15°C	0 in0 mm· —	37%	Clear	WSW 6 mph9 km/h
DayPartly cloudy and warm, with a high of 76°F25°C and morning low of 61°F16°C. Breezy from the WSW at 7 to 9 mph11 to 14 km/h. NightPartly cloudy, with a low around 59°F15°C. Light wind from the SW around 5 mph8 km/h.
	TuesdayAug 25	76°F24°C	59°F15°C	0 in0 mm· —	39%	Clear	WSW 6 mph9 km/h
DayPartly cloudy and warm, with a high of 76°F24°C and morning low of 61°F16°C. Breezy from the WSW at 7 to 9 mph11 to 14 km/h. NightPartly cloudy, with a low around 59°F15°C. Light wind from the SW around 5 mph8 km/h.
	WednesdayAug 26	75°F24°C	58°F14°C	0 in0 mm· —	39%	Clear	WSW 6 mph10 km/h
DayPartly cloudy and warm, with a high of 75°F24°C and morning low of 61°F16°C. Breezy from the WSW at 7 to 9 mph11 to 14 km/h. NightPartly cloudy, with a low around 58°F14°C. Light wind from the SW 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