San Francisco International Airport is a major international airport located 21 km south of downtown San Francisco, California, United States, adjacent to the cities of Millbrae and San Bruno in unincorporated San Mateo County. It is often referred to as SFO.

Climatology

Dry-summer subtropical ”Mediterranean" climate (Köppen climate classification Csb) - characterized by warm, dry summers and mild winters. During the summer, rising hot air in California's interior valleys creates a low pressure area that draws winds from the North Pacific High through the Golden Gate, which creates the city's characteristic cool winds and fog. The fog is less pronounced in eastern neighborhoods and during the late summer and early fall, which is the warmest time of the year.