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      Elev undefined ft, undefined °undefined undefined °undefined

      Castro Valley, CA

      undefined Station57°
      Updated: 9:09 AM PDT on September 23, 2026 (GMT -7)
      5 minutes ago
      82°
      56°
      57
      Feels Like 57
      Mostly Cloudy
      N
      2
      Higher temperature is expected today
      Wundermap
      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 09/24
        High 82°f
         15% Precip. / 0 in
        Some clouds this morning will give way to generally sunny skies for the afternoon. High 82F. Winds WNW at 10 to 15 mph.
        Tonight
        Thu 09/24
        Low 57°f
         18% Precip. / 0 in
        Clear to partly cloudy. Low 57F. Winds NW at 5 to 10 mph.
        Tomorrow
        Fri 09/25
        High 79°f58°f
         19% Precip. / 0 in
        Sunshine and clouds mixed. High 79F. Winds WNW at 10 to 15 mph.
        Hourly Forecast
        Now
        57°
        10AM
        62°
        11AM
        67°
        12PM
        71°
        1PM
        77°
        2PM
        81°
        3PM
        83°
        4PM
        82°
        5PM
        79°
        6PM
        76°
        7PM
        72°
        7:03PM
        Sunset
        8PM
        68°
        9PM
        66°
        10PM
        65°
        11PM
        64°
        12AM
        62°
        1AM
        61°
        2AM
        60°
        3AM
        60°
        4AM
        59°
        5AM
        59°
        6AM
        59°
        6:58AM
        Sunrise
        7AM
        58°
        8AM
        62°
        9AM
        66°
        Precipitation
        20%
        Pollen
        Ragweed Pollen
        Moderate
        Air Quality
        43
        Good
        UV Index
        1
        Low
        Additional Conditions
        1. Pressure 29.94 in
        2. Visibility 9 miles
        3. Clouds Mostly Cloudy
        4. Dew Point54°F
        5. Humidity 90%
        6. Rainfall 0 in
        7. Snow Depth 0 in
         KHWD Station History
        Almanac for September 23, 2026
        1. Forecast Average Record
        2. Temperature
        3. High 82°F 77°F 98°F 1943
        4. Low 56°F 57°F 42°F 1945
        5. Rain/Snow Depth
        6. Precipitation 0 in 3 in -
        7. Snow 0 in 0 in -
        Almanac for September 24, 2026
        1. Forecast Average Record
        2. Temperature
        3. High 79°F 77°F 93°F
        4. Low 56°F 57°F 43°F
        Astronomy
        1. Sun Rise Set
        2. Actual Time 6:57 AM 7:03 PM
        3. Civil Twilight 6:30 AM 7:29 PM
        4. Nautical Twilight 6:00 AM 8:00PM
        5. Astronomical Twilight 5:29 AM 8:30 PM
        1. Length of Visible Light 12h 58m
        2. Length of Day 12h 6m
        3. Tomorrow will be 2 minutes 24 seconds shorter
        1. Moon 5:38 PM 3:45 AM
        2. Waxing Gibbous92% of the Moon is Illuminated
        Sep 26
        Full Moon
        Oct 3
        Waning Half Last Qtr
        Oct 10
        New Moon
        Oct 18
        Waxing Half First Qtr
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