GOLETA – Authorities issued more evacuation orders for homes in the Santa Ynez Mountains Thursday as a wildfire feeding on half-century-old brush shifted direction and threatened additional homes.

The Gap Fire, one of hundreds burning in California, was estimated to have burned 2,400 acres – equivalent of nearly 4 square miles – as it burned for a third day. Containment was estimated at 16 percent.

Authorities said the area hadn't burned since 1955 and some of the chaparral stood 20 feet high.

Mandatory evacuation orders were issued to residents living along West Camino Cielo road and North Patterson Avenue and in the Hidden Valley and Trout Club communities.

“We're staying ahead of the curve to give people enough time to get out without panicking,” Santa Barbara County Fire Capt. Eli Iskow said.

Glen Annie and La Patera canyons remained under mandatory evacuation orders and about 45 people had left.

About 750 firefighters were battling the fire from the air and on the ground as the region's notorious “Sundowner” winds began to blow down from the mountains toward the ocean. Winds gusts were expected to reach 40 mph in the evening, Iskow said.

“There's a lot of ash falling. It looks like snow and it's all over the place,” said Nicole Davidson, 29, manager of a Michaels craft store in Goleta. “You can hear helicopters heading to the fire with water scoops.”

The fire's intensity prompted Goleta's Rotary Club to cancel its 34th annual Fourth of July fireworks display.

Seesawing winds made it hard on firefighters, county Fire Department Capt. Eli Iskow said.

“It's definitely expanded in width; it's taking quite a jump to the east along the mountain ridge ... above populated areas,” he said.

Resources were being stretched by the requirements of some 1,000 other fires in the north, Iskow said.

“We are definitely with competition with all the other fires in the state,” he said. “Aircraft come off those other fires and fly directly to us.”

County fire spokesman Jim Turner predicted that the rough terrain would prevent firefighters from using bulldozers to construct fire lines.

“A lot of it is going to be constructed by hand,” he said.

The firefighting effort has cost $1.6 million, officials said.

Meanwhile, evacuees sought shelter for about 30 pets and 75 horses at a local arena set up by the county animal services department, agency Director Jan Glick said.

Goleta, population about 55,000, is 8 miles west of Santa Barbara.