LOS ANGELES — A wildfire in a wilderness area of central California exploded in size to over 79,600 acres as dry, hot weather raised the fire risk for large portions of the state during the July Fourth holiday.

The Madre Fire became California's largest blaze so far this year, ripping through grasslands after breaking out Wednesday in southeastern San Luis Obispo County. By Sunday morning, the fire had grown to nearly 80,000 acres while containment of the fire grew from 10% to 30%.

Over 1,000 personnel, 10 helicopters, 23 water tenders, 65 engines and more were assigned to the fire Sunday.

Cal Fire also reported that one structure had been destroyed in the blaze.

Evacuation orders and warnings were issued for communities near State Route 166 as flames moved through hilly terrain toward the Carrizo Plain National Monument, about 45 miles east of Santa Maria. The region about 125 miles northwest of Los Angeles contains vast grasslands that draw visitors in the spring to see its wildflowers.

Part of Route 166 East was closed Thursday, and there was "no estimate for re-opening," California Department of Transportation, known as Caltrans, said on social media.

The fire was pushed by summer gusts that typically increase as the sun starts going down, said meteorologist Ryan Kittell with the National Weather Service.

"The winds are pretty light during the day, but they do pick up pretty substantially in the afternoon and evening hours," Kittell said.

He said gusts could reach 40 mph later in the day Thursday, posing new challenges for firefighters working in 95-degree heat.

Dozens of smaller wildfires were burning across the state.

Southern California's Wolf Fire reached 80% containment Sunday after charring more than 2,300 acres of dry brush since breaking out June 29 in Riverside County east of Los Angeles.

Unrelated to the wildfires, a fire burned four homes in the Pacoima neighborhood before being brought under control Thursday night. Fireworks were exploding when crews arrived at the scene, and a woman was transported to a hospital in critical condition, the Los Angeles Times reported.