Current Conditions
Castro Valley, California
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
| Day | 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. | |||||||
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About This Forecast
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Coordinates: 37.6941°N, 122.0863°W·Elevation: 50m·Timezone: America/Los_Angeles·Population: 61,388