Campbell enjoys a Mediterranean climate (Köppen climate classification *Csb*), characterized by warm, dry summers and cool, wet winters. This temperate weather is a hallmark of the Santa Clara Valley and is frequently cited as a major draw for residents.
Summer temperatures typically range from the low 80s to low 90s Fahrenheit (27-33°C), with low humidity and cool evenings thanks to marine breezes filtering over the coastal mountains. Winters are mild, with daytime highs in the upper 50s to low 60s Fahrenheit (14-17°C) and nighttime lows rarely dropping below freezing. Nearly all of the city's annual rainfall—averaging about 15 inches (380 mm)—occurs between November and April. Snow is exceptionally rare on the valley floor. The best times to visit are in the spring and fall when the weather is comfortably warm and the local flora is in full bloom. Like much of California, Campbell is susceptible to natural events such as earthquakes and, indirectly, regional wildfire smoke.