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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: 2:35 PM PDT on September 16, 2026 (GMT -7)
      4 minutes ago
      68°
      56°
      65
      Feels Like 65
      Partly Cloudy
      N
      17
      Gusts 26 mph
      Lower temperature is expected today
      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
        Today
        Thu 09/17
        High 67°f
         2% Precip. / 0 in
        Sunshine and clouds mixed. High 67F. Winds W at 10 to 20 mph.
        Tonight
        Thu 09/17
        Low 59°f
         22% Precip. / 0 in
        Partly cloudy early followed by cloudy skies overnight. Low 59F. Winds WSW at 10 to 15 mph.
        Tomorrow
        Fri 09/18
        High 72°f56°f
         11% Precip. / 0 in
        Cloudy early, becoming mostly sunny in the afternoon. High 72F. Winds WSW at 10 to 15 mph.
        Hourly Forecast
        Now
        67°
        3PM
        67°
        4PM
        66°
        5PM
        65°
        6PM
        63°
        7PM
        62°
        7:14PM
        Sunset
        8PM
        61°
        9PM
        60°
        10PM
        61°
        11PM
        61°
        12AM
        60°
        1AM
        61°
        2AM
        61°
        3AM
        61°
        4AM
        61°
        5AM
        61°
        6AM
        60°
        6:52AM
        Sunrise
        7AM
        60°
        8AM
        61°
        9AM
        62°
        10AM
        64°
        11AM
        66°
        12PM
        67°
        1PM
        69°
        2PM
        71°
        Precipitation
        23%
        Pollen
        Ragweed Pollen
        High
        Air Quality
        36
        Good
        UV Index
        6
        High
        Additional Conditions
        1. Pressure 29.97 in
        2. Visibility 10 miles
        3. Clouds Partly Cloudy
        4. Dew Point53°F
        5. Humidity 62%
        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 68°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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