| Climate Summary (made with AI, use with caution)
 | | Castro Valley, CA Climate Summary Temperature     •   Average annual temperature: 59.1°F (15.1°C)•   Average January temperature: 48.2°F (9°C)
 •   Average July temperature: 70.8°F (21.6°C)
 •   Record high temperature: 109°F (42.8°C)
 •   Record low temperature: 19°F (-7.2°C)
 Precipitation     •   Average annual precipitation: 21.7 inches (551 mm)•   Average number of rainy days: 63
 •   Wettest month: January (4.3 inches)
 •   Driest month: July (0.1 inches)
 Snowfall     •   Average annual snowfall: 0.4 inches (10 mm)•   Average number of days with snow: 0.3
 Humidity     •   Average annual relative humidity: 72%•   Most humid month: January (79%)
 •   Least humid month: August (63%)
 Wind     •   Average annual wind speed: 6.6 mph (10.6 km/h)•   Most windy month: January (7.7 mph)
 •   Least windy month: September (5.6 mph)
 Sunshine     •   Average annual sunshine: 2,900 hours•   Most sunshine: July (330 hours)
 •   Least sunshine: December (170 hours)
 Climate Type     •   Mediterranean climate Köppen Climate Classification     •   Csa (Mediterranean climate with hot, dry summers) Hardiness Zone     •   9b Growing Season     •   Average frost-free period: 270 days (March 15     •   November 12) Climate Summary Castro Valley, CA has a Mediterranean climate with hot, dry summers and mild, wet winters. The average annual temperature is 59.1°F (15.1°C), and the average annual precipitation is 21.7 inches (551 mm). The wettest month is January, with an average of 4.3 inches (109 mm) of rain, and the driest month is July, with an average of 0.1 inches (2.5 mm) of rain. Snowfall is rare in Castro Valley, averaging only 0.4 inches (10 mm) per year. The summers in Castro Valley are hot and dry, with average temperatures in the upper 70s and low 80s Fahrenheit (mid-20s to low 30s Celsius). The humidity is typically low, making the heat feel less oppressive. The winters are mild and wet, with average temperatures in the mid-40s and low 50s Fahrenheit (7-12°C). The humidity is typically higher in the winter, and there is occasional fog. Castro Valley is located in USDA Hardiness Zone 9b, which means that it is suitable for growing a wide variety of plants, including citrus trees, avocados, and bougainvillea. The growing season in Castro Valley is long, averaging 270 days per year. Overall, Castro Valley has a pleasant climate that is ideal for outdoor activities year-round. | 
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 | Facts & Historical Information (made with AI, use with caution)
 Tourist Attractions| | Natural History     •   Castro Valley is home to the Hayward Fault, a major earthquake fault that runs through the East Bay.     •   The valley is also home to the Chabot Space & Science Center, which features exhibits on astronomy, space exploration, and the natural world. Science     •   The Lawrence Livermore National Laboratory, a major research facility, is located in nearby Livermore.     •   The University of California, Berkeley's Seismological Laboratory has a research station in Castro Valley to monitor seismic activity on the Hayward Fault. Personalities     •   Joaquin Castro, the namesake of Castro Valley, was a Mexican military officer who received a land grant in the area in 1834.     •   John Muir, the renowned naturalist and conservationist, visited Castro Valley in 1872 and was impressed by its natural beauty.     •   The actress and singer Doris Day lived in Castro Valley in the 1950s and 1960s. | 
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 Nearby Cities:| | 1.Lake Chabot Regional Park: A scenic park featuring a large lake for fishing, boating, and swimming, as well as hiking trails, picnic areas, and a nature center. 2.Redwood Regional Park: A vast park known for its towering redwood trees, offering hiking trails, picnic areas, and a visitor center with exhibits on the park's history and ecology. 3.Castro Valley Community Center: A multipurpose facility that hosts a variety of events, classes, and programs, including fitness classes, art exhibitions, and community gatherings. | 
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