Strike teams in Sonoma and Alameda counties left before the sun came up to help more than 2,300 personnel who are already fighting the Jesusita Fire.
Alameda County Fire Department spokeswoman Aisha Knowles said the county sent its third team this morning, with firefighters from the county, Union City, Fremont and Camp Parks fire departments.
About 50 personnel from Alameda County have been deployed since Tuesday, Knowles said.
Sonoma County fire dispatch supervisor Ron Marsh said a strike team with about 20 personnel from six fire departments left around 5:30 a.m.
The firefighters typically work 24-hour shifts when they are deployed and then fix equipment and rest for the next 24 hours, he said. They make an initial commitment that could last up to 14 days, depending on the fire's development.
Firefighters from all over the Bay Area have been sent down to the Jesusita Fire, which has prompted the closure of at least 24 schools and injured 11 firefighters. The blaze was 10 percent contained this morning.
According to Santa Barbara County assistant spokesman Richard Morgantini, residents from 30,500 homes have been required to evacuate and 23,000 are in a warning area.
People who need help with shelter can call the American Red Cross at (805) 687-1331.
The county's command center had to evacuate, and the general inquiry number was not working this morning but was expected to be running sometime this afternoon, he said. That number is (805) 681-5197.