The fire began Wednesday and exploded to 10,000 acres in just a few hours.

A wildfire that broke out in Los Angeles earlier this week has spread to 11,000 acres as of Friday, according to authorities.

The Lake Fire, which grew to 10,000 acres in just a few hours on Wednesday, was more contained than it had been at 12%.

Cal Fire said that crews took advantage of improved weather conditions, with slightly lower temperatures and moisture from tropical storm Elida to battle the blazes.

However, “near critical fire weather” could develop later in the afternoon when warmer and drier conditions move through the area, according to Cal Fire.

No injuries have been reported yet, but officials said 5,420 structures were threatened and at least 100 structures were affected by the evacuation orders, according to ABC Los Angeles station KABC.

The fire, which broke out near the intersection of North Lake Hughes Road and Pine Canyon Road, has burned in some areas that have not burned since 1968, according to officials who spoke with KABC.

Evacuations orders have been in place for residents in the area.

ABC News’ Bonnie McLean contributed to this report.