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Castro Valley/Eden ChamberCastro Valley, CA Weather Forecast
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Castro Valley Weather Forecast
| REST OF TONIGHT | SATURDAY | SATURDAY NIGHT | SUNDAY | SUNDAY NIGHT | MONDAY | MONDAY NIGHT | TUESDAY | TUESDAY NIGHT | WEDNESDAY | THURSDAY | FRIDAY |
 |  | | | | |  |  | | | | |
| Partly Cloudy | Partly Cloudy | Partly Cloudy | Partly Cloudy | Partly Cloudy | Partly Cloudy | Clear | Sunny | Clear | Mostly Clear | Mostly Clear | Mostly Clear |
| Lo: 55°FLo: 13°C | Hi: 70°FHi: 21°C | Lo: 55°FLo: 13°C | Hi: 67°FHi: 19°C | Lo: 55°FLo: 13°C | Hi: 75°FHi: 24°C | Lo: 55°FLo: 13°C | Hi: 76°FHi: 24°C | Lo: 59°FLo: 15°C | Hi: 76°FHi: 24°C Lo: 59°FLo: 15°C | Hi: 76°FHi: 24°C Lo: 59°FLo: 15°C | Hi: 76°FHi: 24°C Lo: 59°FLo: 15°C |
POP = Probability of Precipitation.
Weather Outlook Updated: 902 PM PDT Fri Sep 25 2026 
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Issued: 847 PM PDT Fri Sep 25 2026
Key Messages
Updated at 1238 PM PDT Fri Sep 25 2026- Cooler conditions through the weekend
- Warmer temperatures next week
Aviation
... (06Z TAFS) Issued at 840 PM PDT Fri Sep 25 2026
VFR is expected to prevail for a majority of the forecast period for all terminals. Monterey Bay has a chance of IFR/LIFR fog/stratus developing late in the overnight period, with low confidence in timing and extent.
Vicinity of SFO...VFR conditions expected through a majority of the forecast period with gusty winds easing...