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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 Station65°
      Updated: 5:25 PM PDT on September 16, 2026 (GMT -7)
      10 minutes ago
      67°
      55°
      65
      Feels Like 65
      Partly Cloudy
      N
      16
      Gusts 26 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 57°f
         34% Precip. / 0 in
        Partly cloudy skies during the evening giving way to a few showers after midnight. Low 57F. Winds WSW at 10 to 20 mph. Chance of rain 30%.
        Tomorrow
        Fri 09/18
        High 73°f
         20% Precip. / 0 in
        Cloudy early, becoming mostly sunny in the afternoon. High 73F. Winds WSW at 10 to 15 mph.
        Tomorrow night
        Fri 09/18
        Low 54°f
         22% Precip. / 0 in
        Partly cloudy. Low 54F. Winds WNW at 10 to 15 mph.
        Hourly Forecast
        Now
        62°
        6PM
        61°
        7PM
        60°
        7:14PM
        Sunset
        8PM
        59°
        9PM
        60°
        10PM
        60°
        11PM
        60°
        12AM
        60°
        1AM
        61°
        2AM
        61°
        3AM
        61°
        4AM
        61°
        5AM
        61°
        6AM
        61°
        6:52AM
        Sunrise
        7AM
        61°
        8AM
        61°
        9AM
        63°
        10AM
        64°
        11AM
        66°
        12PM
        68°
        1PM
        69°
        2PM
        71°
        3PM
        72°
        4PM
        72°
        5PM
        71°
        Precipitation
        24%
        Pollen
        Ragweed Pollen
        Moderate
        Air Quality
        31
        Good
        UV Index
        1
        Low
        Additional Conditions
        1. Pressure 29.97 in
        2. Visibility 10 miles
        3. Clouds Partly Cloudy
        4. Dew Point52°F
        5. Humidity 71%
        6. Rainfall 0 in
        7. Snow Depth 0 in
         KHWD Station History
        Almanac for September 17, 2026
        1. Forecast Average Record
        2. Temperature
        3. High 67°F 78°F 94°F 1968
        4. Low 55°F 58°F 43°F 1946
        5. Rain/Snow Depth
        6. Precipitation 0 in 3.2 in -
        7. Snow 0 in 0 in -
        Almanac for September 18, 2026
        1. Forecast Average Record
        2. Temperature
        3. High 73°F 77°F 91°F
        4. Low 55°F 58°F 43°F
        Astronomy
        1. Sun Rise Set
        2. Actual Time 6:51 AM 7:12 PM
        3. Civil Twilight 6:25 AM 7:38 PM
        4. Nautical Twilight 5:54 AM 8:09PM
        5. Astronomical Twilight 5:23 AM 8:40 PM
        1. Length of Visible Light 13h 13m
        2. Length of Day 12h 20m
        3. Tomorrow will be 2 minutes 24 seconds shorter
        1. Moon 1:44 PM 10:50 PM
        2. Waxing Crescent40% 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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