One wind-driven brush fire erupted near La Costa Country Club in Carlsbad and forced the evacuation of an elementary school, a park and homes.
Another fire, at Camp Pendleton, was discovered shortly before 10 a.m. Wednesday and forced evacuations of the De Luz housing area, Mary Fay Pendleton Elementary School and the Naval Weapons Station Fallbrook, which is on the northeast edge of the sprawling base.
An evacuation center was established at the Paige Fieldhouse on the base.
The fire does not pose a danger to the city of Fallbrook.
There was no immediate estimate of how large either fire was as crews attacked from above with water-dropping aircraft, and on the ground.
The San Diego region, like much of the rest of the Southland, was dealing with a stifling record-breaking heat wave that, combined with high winds and tinder-dry brush, had created days of extreme fire danger.
Firefighters on Wednesday also increased containment of the Miguelito fire in Santa Barbara County, estimated at 600 acres, to 50%.