Wildfire Erupts in Orange County, Forcing Evacuations

A brush fire that erupted on Monday afternoon in the hills of Orange County in Southern California exploded to nearly 2,000 acres within a few hours, prompting evacuation orders for nearby communities as the blaze burned uncontrolled.

Known as the Airport fire, it began just before 1:30 p.m. about 15 miles east of Irvine, Calif., near an airport for remote-controlled model airplanes. Officials have ordered evacuations in parts of Trabuco Canyon, a community in the foothills of the Santa Ana Mountains, and have recommended evacuations for surrounding neighborhoods as well.

The fire broke out during a prolonged heat wave that has pushed temperatures in many parts of Southern California into the triple digits in recent days. A fire in the San Bernardino Mountains that began on Thursday, about 55 miles northeast of Trabuco Canyon, has swelled to threaten more than 33,000 structures and is only 5 percent contained.

In Trabuco Canyon, temperatures reached about 98 degrees on Monday, above normal for early September, said Samantha Zuber, a meteorologist with the National Weather Service in San Diego. Wind speeds were about 15 miles per hour, she said.

The winds are expected to slow into the evening, but overnight temperatures will remain unusually high, unlikely to drop below 70 degrees, she said. Similar conditions have been fueling wildfires in the state all summer. “Unfortunately, temperatures won’t cool that much,” Ms. Zuber said.

She said that temperatures in the fire zone would begin to drop on Tuesday — a high of 95 is expected — before a significant cool down, which is forecast to start on Wednesday and continue for the rest of the week.