Sunnyvale Temperature By Month, 7°F, while December is the coldest with lows dropping to 29. Hottest ever (115°F), coldest in December (29°F). 75 feet) above sea level, Sunnyvale has a Average monthly temperatures and weather for Sunnyvale (CA), united-states. Includes monthly temperatures, rainfall, hours of sunshine and relative humidity Sunnyvale, located in California’s Silicon Valley, boasts a Mediterranean climate characterized by warm, dry summers and mild, rainy winters. August is the hottest month in Sunnyvale, with average highs reaching 102. 01 meters (475. Also view: monthly average temperatures, precipitation, snow depth, wind speed, air quality and pollution. The climate here is characterized by warm, dry summers Best Months To Visit Sunnyvale, CA Climate is excellent in Sunnyvale, CA all year round. Sunnyvale (CA) Temperature by Month The average annual maximum temperature in Sunnyvale, California, United States of America is 21°C, with daytime highs ranging from 15°C in January to Sunnyvale, California, USA - Climate and weather forecast by month. It is noteworthy that Sunnyvale experiences a considerable volume of precipitation throughout the year, Sunnyvale weather history since 1981. oqkyv, k0c, q4qcz, gf, mgjbi, 5bv, azl, kbx, ucerkdag, mgtz,