SAN DIEGO - A fire of unknown origin blackened swaths of rugged open terrain near Jamul Wednesday amid unseasonable heat and arid Santa Ana conditions.
Temperatures were in the low 90s, the humidity was hovering around 15 percent and winds out of the east were gusting up to 25 mph when the blaze began spreading off the 18400 block of Deerhorn Valley Road about 2 p.m., according to the National Weather Service.
Ground crews and personnel aboard firefighting planes and helicopters had the flames under control within 90 minutes, Cal Fire Kendal Bortisser said.
The roughly three-acre blaze never posed any imminent structural threats but left a man with complaints of respiratory irritation due to smoke inhalation. Medics treated him at the scene.
Firefighters planned to remain in the area overnight to make sure all hot spots were thoroughly doused, Bortisser said.
The cause of the blaze was under investigation.