BONSALL, Calif. – The Lilac Fire continued to burn overnight in North County, although it didn't grow beyond 4,100 acres, officials said Sunday.
Santa Anas failed to show overnight, giving firefighters an assist as they etched fire lines around 75 percent of the blaze as of 7 p.m. Sunday.
More than 1,400 fire personnel entered the fourth day of battling the flames.
"Firefighters continue to improve and increase the containment lines," said the morning Cal Fire assessment, which added that the weather "has been favorable for firefighters."
The blaze has destroyed at least 151 structures and damaged 50 others.
Thousands of North County residents fled their homes after the fire broke out around 11:15 a.m. on Thursday, just west of Interstate 15 and north of Lilac Road in Pala Mesa, amid gusty, arid winds.
About 110 people who remain evacuated from their homes due to the fire have been consolidated to two shelters: Palomar College in San Marcos and Bostonia Park and Recreation Center in El Cajon, according to San Diego County.
Large animals were sheltered at the Del Mar Fairgrounds.
The number of acres affected by the fire has remained steady since Thursday night. Since then, firefighters have been working to increase the containment of the fire -- reducing the number of hot spots that could reignite when fanned by Santa Ana winds.
Crews have largely transitioned their efforts from the air to the ground, he said. Strong winds are expected to continue Sunday. A Red Flag Warning issued by the National Weather Service is in effect until 8 p.m. The strongest winds are expected in the San Diego County mountains and foothills, with gusts over 60 mph, accord to the NWS.
The winds, coupled with humidity levels below 15 percent, make for prime fire conditions.
"Winds will diminish steadily from Sunday afternoon through Sunday night, and the critical fire weather conditions will wane Sunday night," the NWS said. "However, offshore flow will prevail through next week and continue very low humidity and occasional local gusty winds, though current indications are that we will have elevated versus critical fire weather conditions most of the week."
People should avoid activities that could cause fires, authorities said. That includes keeping vehicles off dry grass, practicing safe towing, avoiding activities with open flames, properly discarding cigarettes and obeying burn bans.
State damage assessment teams have begun their inspections, and damaged and destroyed numbers are likely to change, authorities said.