A massive blaze in Southern California has continued to spread and is now the fifth-largest wildfire in the state's history.

The Thomas fire, centered on the Santa Barbara area, had spread across 231,700 acres by Monday evening — a little less than half the size of Rhode Island. As of Monday, the fire destroyed 794 buildings and was 20% contained.

Another 18,000 structures were still in harm's way, including homes of some of the area's high-profile celebrity residents. Officials have said they worry the blaze could worsen because of wind gusts and predicted dry conditions for the next week.

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"We've had events like this in Southern California over the years, but this is more intense and it's longer. We're seeing dry weather forecast well through this week down in Southern California and maybe beyond," Chief Ken Pimlott, who heads the California Department of Forestry and Fire Protection, told California Public Radio. The dryness mixed with gusty winds are the makings for a "catastrophic fire," he said.

Cal Fire tweet

One woman died in a car crash while fleeing the fires. On Sunday, one of the nearly 6,400 firefighters working to contain the growing fire broke his leg.

Santa Barbara County, which calls itself "the American Riviera" and lies northwest of Los Angeles, is a popular area for the stars.

Wearing a face mask and showing the smoke surrounding his home, actor Rob Lowe recorded a video as he evacuated his Santa Barbara house.