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Personalized Forecasts

Featured Forecast

My Favorite Forecasts

    My Recent Locations

    • Early AM

      Sep 21

      55° Lo
      Clear
      • Stargazing
      • Weather
      • Cloud Cover: 51%
      • Precip: 2%
      • Hours of Precip: 0
      More
    • Today

      Sep 21

      68° /54°
      Mostly sunny and pleasant
      • Very Good
      • for stargazing
      • Cloud Cover: 25%
      • Precip: 3%
      • Hours of Precip: 0
      More
    • Fri

      Sep 22

      71° /52°
      Plenty of sun, but cool
      • Excellent
      • for stargazing
      • Cloud Cover: 9%
      • Precip: 0%
      • Hours of Precip: 0
      More
    • Sat

      Sep 23

      76° /52°F
      Sunny and pleasant
      • Excellent
      • for stargazing
      • Cloud Cover: 0%
      • Precip: 0%
      • Hours of Precip: 0
    • Sun

      Sep 24

      79° /54°
      Sunny and delightful
      • Very Good
      • for stargazing
      • Cloud Cover: 38%
      • Precip: 0%
      • Hours of Precip: 0
      More
    72°/56° RealFeel® 81°/60°
    Sunny
    • Winds from the S
    • 5 mph
    • Precipitation: 0%
    • Rain: 0 in
    • Snow: 0 in
    • Humidity: 51%
    • Cloud Cover: 13%
    • Dew Point: 46° F
    • Visibility: 10 mi

    Temperature History

    more Historical Weather Data >
      Today Normal Record 9/23/2016
    High 76° 77° N/A 70°
    Low 52° 55° N/A 53°

    Sunrise/Sunset

    • Sunrise: 6:57 AM
    • Sunset: 7:04 PM
    • Duration: 12:07 hr

    Moonrise/Moonset

    • Moonrise: 10:17 AM
    • Moonset: 9:24 PM
    • Duration: 11:07 hr
    Astronomy

    Solunar Information for Castro Valley, CA

    Thu, Sep 28
    First
    Thu, Oct 5
    Full
    Thu, Oct 12
    Last
    Thu, Oct 19
    New

    Sat. Stargazing