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      Small Craft Advisory
      until 9:00 PM PDT
      Elev 436 ft, 37.714 °N 122.061 °W

      Castro Valley, CA

      Ridges Station62°
      Updated: 4:40 PM PDT on September 16, 2026 (GMT -7)
      5 minutes ago
      67°
      56°
      62
      Feels Like 62
      Partly Cloudy
      N
      19
      Gusts 31 mph
      Higher temperature is expected tomorrow
      50
      50
      575
      90
      50
      7
      0 mph
      50
      50
      50
      50
      50
      50
      Radar · Now
        Hyper-local data from Weather Underground's network of
        400,000+ personal weather stations worldwide
        Tonight
        Thu 09/17
        Low 58°f
         24% Precip. / 0 in
        Partly cloudy skies early will give way to cloudy skies late. Low 58F. WSW winds at 15 to 25 mph, decreasing to 5 to 10 mph.
        Tomorrow
        Fri 09/18
        High 73°f
         11% Precip. / 0 in
        Morning clouds will give way to sunshine for the afternoon. High 73F. Winds WSW at 10 to 15 mph.
        Tomorrow night
        Fri 09/18
        Low 56°f
         21% Precip. / 0 in
        A few clouds. Low 56F. Winds WNW at 10 to 15 mph.
        Hourly Forecast
        Now
        63°
        5PM
        63°
        6PM
        61°
        7PM
        61°
        7:14PM
        Sunset
        8PM
        61°
        9PM
        60°
        10PM
        60°
        11PM
        60°
        12AM
        60°
        1AM
        60°
        2AM
        60°
        3AM
        60°
        4AM
        60°
        5AM
        60°
        6AM
        60°
        6:52AM
        Sunrise
        7AM
        59°
        8AM
        60°
        9AM
        62°
        10AM
        63°
        11AM
        66°
        12PM
        67°
        1PM
        69°
        2PM
        71°
        3PM
        72°
        4PM
        72°
        Precipitation
        24%
        Pollen
        Ragweed Pollen
        High
        Air Quality
        32
        Good
        UV Index
        2
        Low
        Additional Conditions
        1. Pressure 29.97 in
        2. Visibility 10 miles
        3. Clouds Partly Cloudy
        4. Dew Point52°F
        5. Humidity 69%
        6. Rainfall 0 in
        7. Snow Depth 0 in
         KHWD Station History
        Almanac for September 16, 2026
        1. Forecast Average Record
        2. Temperature
        3. High 67°F 78°F 102°F 1971
        4. Low 56°F 58°F 45°F 1944
        5. Rain/Snow Depth
        6. Precipitation 0 in 3.2 in -
        7. Snow 0 in 0 in -
        Almanac for September 17, 2026
        1. Forecast Average Record
        2. Temperature
        3. High 73°F 78°F 94°F
        4. Low 56°F 58°F 43°F
        Astronomy
        1. Sun Rise Set
        2. Actual Time 6:51 AM 7:14 PM
        3. Civil Twilight 6:24 AM 7:40 PM
        4. Nautical Twilight 5:54 AM 8:11PM
        5. Astronomical Twilight 5:22 AM 8:42 PM
        1. Length of Visible Light 13h 15m
        2. Length of Day 12h 23m
        3. Tomorrow will be 2 minutes 24 seconds shorter
        1. Moon 12:45 PM 10:06 PM
        2. Waxing Crescent31% of the Moon is Illuminated
        Sep 18
        Waxing Half First Qtr
        Sep 26
        Full Moon
        Oct 3
        Waning Half Last Qtr
        Oct 10
        New Moon
        Precipitation
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