The deaths of two tourists at Joshua Tree National Park on Monday, believed to be the result of heat exposure, have prompted officials to heighten warnings as the region faces what could be the hottest weekend of the summer.

The bodies of Augustinus Van Hove, 44, and Helena Nuellett, 38, were discovered Monday evening along a sandy, low-lying road near the eastern edge of the park, authorities said. Temperatures had soared as high as 105 that afternoon.

Van Hove, a well-known music promoter in his native Netherlands, had been vacationing in the Coachella Valley with Nuellett, his girlfriend. A popular venue he managed in the city of Tilburg announced his death Wednesday in a post on its website.

A spokeswoman for the Riverside County Sheriff’s Department said the cause of the deaths was still being determined, but evidence indicates the victims “both succumbed due to exposure to the elements.”


The National Weather Service on Wednesday issued a hazardous weather outlook for Southern California as forecasters projected temperatures over 100 in the inland valleys and even higher in desert areas.

At Joshua Tree, a 1,250-square-mile park that covers parts of the Mojave and Colorado deserts, rangers met to discuss ways to better inform visitors of the dangers that come with such extreme heat.

“People should have a plan,” said Joe Zarki, a public information officer at the park. “When you’re traveling out there in your car, you’ve got the AC going, you feel pretty protected and secure. You never really feel like you’re 10 minutes away from a dangerous situation … but that can all change at a moment’s notice.”

Van Hove and Nuellett, who was from Neu-Ulm, Germany, were driving a rental car when they entered the park about noon Monday, according to Sheriff’s Department Cpl. Courtney Donowho.


The pair turned onto Black Eagle Mine Road, a seldom-used dirt road that runs just north of the park’s largest mountain range. Signs warn that only four-wheel-drive vehicles should use it because of its sandy surface.

Investigators believe the rental car, a Dodge Charger sedan, became stuck at some point Monday afternoon.

Van Hove’s body was found about six miles west of the car at 7 p.m.; Nuellett’s body was discovered later by deputies about a mile away from Van Hove’s.

Zarki, the park ranger, said it was likely that after their car got stuck, the couple tried to trek back to a main thoroughfare. He said cellphone coverage in the park is very limited.


“You need to be somewhat self-reliant in these remote locations,” he said. “When you’re out on that road, you’re by yourself.”

Zarki said park visitors should always carry water on their person and “make sure their car is in very good working order.”

Stuart Seto, a specialist at the National Weather Service, urged Southern California residents to take additional precautions this weekend because of the expected heat. Some areas of Los Angeles County, such as Woodland Hills, Palmdale and the Antelope Valley, could reach a “critical heat threshold” of above 105 degrees, he said. The Palm Springs area could see temperatures topping 118 degrees.

The temperatures are part of a dominant high pressure system that will continue over the region until Sunday, Seto said. They are likely to peak Friday and continue through the early part of next week.


“We want to grab people’s attention, to let people know to be safe,” he said.

Los Angeles County Fire Inspector Don Kunitomi said there was an increased chance of wildfires this week. Several brush fires broke out in the Inland Empire earlier this week as temperatures rose. But Kunitomi said the risk will heighten further in the fall as conditions get dryer.

sam.allen@latimes.com