Los Angeles Fire Department spokeswoman Margaret Stewart said the area was hit with erratic winds.

“Those erratic wind gusts were throwing embers for multiple miles ahead of the fire, and that’s really what caused the rapid spread of the fire.”

“However, with these erratic winds and this PDS, or particularly dangerous situation, the winds were constantly changing.”

The weather service warned that foothills facing the south could face erratic winds, “which may lead to chaotic fire growth.”

The weather service warned that winds “will be gusty and erratic, with lulls between gusts.”