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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: 6:38 PM PDT on September 16, 2026 (GMT -7)
      3 minutes ago
      67°
      55°
      62
      Feels Like 62
      Partly Cloudy
      N
      14
      Gusts 23 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
         32% Precip. / 0 in
        Partly cloudy skies this evening. A few showers developing late. Low 58F. Winds WSW at 10 to 20 mph. Chance of rain 30%.
        Tomorrow
        Fri 09/18
        High 71°f
         21% Precip. / 0 in
        Cloudy skies early, followed by partial clearing. High 71F. Winds WSW at 10 to 15 mph.
        Tomorrow night
        Fri 09/18
        Low 55°f
         24% Precip. / 0 in
        A few clouds from time to time. Low near 55F. Winds WNW at 10 to 15 mph.
        Hourly Forecast
        Now
        63°
        7PM
        62°
        7:14PM
        Sunset
        8PM
        61°
        9PM
        61°
        10PM
        60°
        11PM
        60°
        12AM
        60°
        1AM
        61°
        2AM
        60°
        3AM
        60°
        4AM
        59°
        5AM
        33%
        59°
        6AM
        59°
        6:52AM
        Sunrise
        7AM
        59°
        8AM
        60°
        9AM
        61°
        10AM
        63°
        11AM
        65°
        12PM
        66°
        1PM
        68°
        2PM
        70°
        3PM
        70°
        4PM
        71°
        5PM
        70°
        6PM
        68°
        Precipitation
        33%
        Pollen
        Ragweed Pollen
        High
        Air Quality
        31
        Good
        UV Index
        0
        Low
        Additional Conditions
        1. Pressure 29.98 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 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 72°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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