The Oakland Hills Firestorm occurred on Sunday October 20, 1991. The fire is often referred to as the East Bay Hills fire, since it struck the hills in both Oakland and Berkeley, California. The fire killed 25 people and injured 150, as well as destroyed 2,449 single-family dwellings and 437 apartment and condominium units. The economic loss has been estimated at $1.5 billion.

Among the contributing factors that lead to the firestorm were foehn winds (regionally called Diablo winds), which are hot dry winds that blow off shore (over land and then out to sea). Thick, dry vegetation close to many dwellings also contributed to the firestorm.

The Oakland Hills Firestorm was one of several fire disasters that have occurred with regularity in the San Francisco Bay Area. The first was the fire following the earthquake of 1906 in the 60-year old city of San Francisco. Twenty years later a fire in the hills of Berkeley nearly leveled that community. A succession of hill fires burned smaller areas of the Oakland hills in the 1970s and 1980s as construction of homes continued in the area, creating a densely populated residential area on steep hillsides at the edge of an extensive open space parkland (Tilden Park).