More than 6,000 firefighters were battling at least 15 large wildfires across California on Tuesday, prompting evacuations as high temperatures and dried out vegetation fueled dozens of blazes in the Western United States, fire officials said.

Hundreds of people have been ordered to evacuate the remote canyons affected by the largest blaze, the Alamo Fire, which has scorched nearly 29,000 acres (11,736 hectares) of Santa Barbara and San Luis Obispo counties since it started on Thursday.

That blaze was 20-percent contained by Tuesday, according to fire officials, who warned that hot and dry weather that makes it easier for wildfires to spread was expected to continue through the week.

At least four people have been injured and more than 40 buildings damaged or destroyed by the California wildfire, with another 5,500 buildings in harm’s way, according to state fire officials.

“There are evacuations in place and firefighters are contending with steep, rugged terrain providing challenges for them,” California Department of Forestry and Fire Protection spokeswoman Amy Head said in a video statement on Monday.

Further north, the Schaeffer Fire, which began in late June, has burned nearly 15,000 acres (6,070 hectares) in Tulare County. It was only 11 percent contained by Tuesday.

The blazes were among 53 uncontained large fires burning in western states, according to the National Weather Service.

“This week, we’re forecast to see the hot and dry weather from this weekend continue,” Head said. “Winds were expected to be mild in most areas with pockets of 20 to 30 miles per hour winds in the northeast part of the state.”

The U.S. fires so far have been less disruptive than those in Canada’s British Columbia province, which have forced 14,000 people from their homes and disrupted logging and mining operations.

(Reporting by Gina Cherelus in New York; Editing by Nick Zieminski)