Hikers Missing in Joshua Tree Park Amid Soaring Temperatures

Dozens of rescuers are scouring Joshua Tree National Park in Southern California amid intense heat for two hikers who were reported missing on Friday.

Rachel Nguyen, 20, of Westminster, California, and Joseph Orbeso, 21, of Lakewood, California, set out for a hike on Thursday, said Joshua Tree National Park spokesman George Land. The mercury there hit 100 degrees Fahrenheit that day.

When the couple hadn't returned by the next day, the owner of the Airbnb where they were staying grew concerned and called police. Rangers found the hikers' car at a parking lot at the head of a popular trail called Maze Loop on Friday. A "ping" of Orbeso's cellphone was recorded from inside the park on Thursday, said Land.

Rescuers thought they spotted tracks near the vehicle heading north into a canyon, and while dogs seemed to pick up on a scent, they were unable to find anything, according to a statement by Joshua Tree National Park Search & Rescue, a volunteer group.

Two airplanes, two helicopters, six canine tracking teams and up to 100 ground searchers are assisting in the search. They have already covered "thousands of miles," said Land.

On Monday, several rescuers were overcome by the heat. One rescuer as well as canine units had to be airlifted out of the park, said Joshua Tree National Park Search & Rescue.

The San Bernardino County Sheriff's Department had to pull their searchers out of the field by noon Tuesday due to the extreme heat, said spokeswoman Jodi Miller.

They expect to return to the field Wednesday at least in the morning when it is cooler, Miller said.

San Bernardino County Sheriff's Emergency Management team tweeted Tuesday, "Over 50 dedicated searchers from 3 counties and the US Border Patrol brave 110 deg temps to continue the search."

Triple-digit temperatures are common in Joshua Tree National Park during this time of year. Land said it is essential for hikers to take special precautions, like starting out early when it is cooler, taking more water than one thinks is necessary, and letting somebody know the hiking plan.

Land said it was rare for hikers to succumb to the heat in the park, which is 800,000 acres of desert visited by more than 2 million people a year -- but it does happen.

Last August, a 56-year-old female hiker died after suffering from heat-related symptoms on a 100-degree day.

Highs on Wednesday are once again expected to hit the triple digits, as the search for Nguyen and Orbeso goes on.

"We are continuing the search until at least the end of the week," said Land.