The Loma Fire burning in the Santa Cruz Mountains is 50 percent contained at 4,345 acres, Cal Fire officials said Friday evening.
The wildfire, which grew slightly Friday, began around 2:45 p.m. Monday near Loma Prieta and Loma Chiquita roads in southern Santa Clara County, 10 miles northwest of Morgan Hill.
The blaze has destroyed 12 homes and 16 outbuildings and damaged one other home.
It is currently threatening 325 other structures, according to Cal Fire officials.
More that 2,000 fire personnel are fighting the blaze using 177 fire engines, six air tankers, 16 helicopters, 18 bulldozers and 37 water tenders, Cal Fire officials said.
Dry fuels from several years of drought continued to challenge firefighters in inaccessible and steep terrain. Firefighters were planning to reinforce containment lines tonight and limit the potential for spot fires as winds increase.
Mandatory evacuation orders are in effect for the Loma Prieta ridgeline area, including all tributary roads along Summit Road from Soquel San Jose Road to Ormsby Fire Station. This includes Uvas Canyon County Park, Loma Chiquita, Casa Loma and Loma Prieta Way, Cal Fire officials said.
Parts of Croy Road are under an evacuation warning.
An evacuation center is operating at Morgan Hill Presbyterian Church at 16970 De Witt Ave. in Morgan Hill.
All evacuation orders and warnings in Santa Cruz County were lifted Thursday.
Road closures include Loma Chiquita Road one mile east of Highland Way, Summit Road at Ormsby Cutoff, Croy Road three miles west of Uvas Road, Casa Loma and McKean Road, Cal Fire officials said.
Southeasterly winds have sent smoke from the fire into Santa Clara County and other parts of the Bay Area that has affected air quality, according to the Bay Area Air Quality Management District.
Air district officials recommend residents limit their time outdoors, close windows and doors while indoors and prevent outside air from entering by changing settings on their air conditioning units and car ventilation systems to recirculate air.
Smoke exposure can lead to irritated eyes, coughing, scratchy throat and inflamed sinuses, district officials said.
Increased smoke is expected to spread through the county in the coming days and week, according to Santa Clara County public health officials.
Older adults, children and people with respiratory issues are advised to limit their time outdoors when they see or smell smoke, public health officials said.
Santa Cruz County public health officials are also keeping an eye on the air quality.
Anyone experiencing repeated coughing, tightness or pain in their chest, wheezing, difficulty breathing or nausea should contact their medical provider, public health officials said.
The cause of the fire is under investigation.