, °F

Personalized Forecasts

Featured Forecast

My Favorite Forecasts

    My Recent Locations

    • Today

      Aug 21

      74° /61°
      Low clouds break for some sun
      • Good
      • for stargazing
      • Cloud Cover: 60%
      • Precip: 3%
      • Hours of Precip: 0
      More
    • Tue

      Aug 22

      74° /59°
      Nice with plenty of sun
      • Fair
      • for stargazing
      • Cloud Cover: 65%
      • Precip: 0%
      • Hours of Precip: 0
      More
    • Wed

      Aug 23

      75° /57°F
      Clouds, then sun
      • Very Good
      • for stargazing
      • Cloud Cover: 26%
      • Precip: 0%
      • Hours of Precip: 0
    • Thu

      Aug 24

      72° /56°
      Low clouds, then sunshine
      • Excellent
      • for stargazing
      • Cloud Cover: 19%
      • Precip: 0%
      • Hours of Precip: 0
      More
    • Fri

      Aug 25

      75° /56°
      Low clouds, then sun
      • Excellent
      • for stargazing
      • Cloud Cover: 1%
      • Precip: 0%
      • Hours of Precip: 0
      More

    Day

    75°Hi RealFeel® 79° Precipitation 0%
    Cool with low clouds giving way to sunshine
    • Winds from the
    • WSW 9 mph
    • Gusts: 15 mph
    • Max UV Index: 10 (Extreme)
    • Thunderstorms: 0%
    • Precipitation: 0 in
    • Rain: 0 in
    • Snow: 0 in
    • Ice: 0 in
    • Hours of Precipitation: 0 hrs
    • Hours of Rain: 0 hrs

    Night

    57°Lo RealFeel® 56° Precipitation 0%
    Partly cloudy
    • Winds from the
    • SW 7 mph
    • Gusts: 13 mph
    • Max UV Index: N/A
    • Thunderstorms: 0%
    • Precipitation: 0 in
    • Rain: 0 in
    • Snow: 0 in
    • Ice: 0 in
    • Hours of Precipitation: 0 hrs
    • Hours of Rain: 0 hrs

    Temperature History

    more Historical Weather Data >
      Today Normal Record 8/23/2016
    High 75° 78° N/A 76°
    Low 57° 57° N/A 56°

    Sunrise/Sunset

    • Sunrise: 6:31 AM
    • Sunset: 7:51 PM
    • Duration: 13:20 hr

    Moonrise/Moonset

    • Moonrise: 8:31 AM
    • Moonset: 9:16 PM
    • Duration: 12:45 hr
    Astronomy

    Solunar Information for Castro Valley, CA

    Mon, Aug 21
    New
    Tue, Aug 29
    First
    Wed, Sep 6
    Full
    Wed, Sep 13
    Last

    Wed. Stargazing