An animal sanctuary was among those threatened by the fire. Animals, including bears, chimpanzees and bison, were being moved from the sanctuary by Saturday, according Wildlife Waystation, the group that runs it.
However, there was good news Saturday evening: The winds had changed direction and firefighters had contained the blaze near the facility, the group said. "They have ceased evacuation of the rest of the animals, as they have been deemed SAFE!!" Wildlife Waystation said on Facebook.
"One wind shift and this whole place could be gone in half an hour," a resident who fled his home, Chris Freeman, told NBC News.
The smoke and flames were seen for miles around. Ash fell on cars in Pasadena and on beaches in Malibu. The smoke created unhealthy air conditions in large parts of the Los Angeles area, and prompted warnings from health officials. Santa Clarita is about 35 miles north of downtown Los Angeles.
"The fire weather and the typical temperatures this year this summer are projected to be higher than normal so it's important that all of our citizens recognize that," Los Angeles Fire Department Chief Daryl Osby said.
The fire began by the 14 Freeway, Osby said, and a cause is under investigation. Ninety percent of wildfires are caused by humans, he said.
California is in its fifth year of a historic drought, creating dry vegetation especially susceptible to catching fire. High temperatures in Southern California and windy conditions were not helping. Some fields have not burned for decades, he said.
The area is under a "red flag warning," meaning critical wildfire conditions exist, until Sunday night, the National Weather Service said.
"Probably five years ago, based on our fire behavior, if we had a similar fire we would have probably caught this fire at the ridge," Osby said.
The cause of the fire is under investigation.