Photos: Death Valley visitors drawn to the hottest spot on Earth during ongoing US heat wave

As uninviting as it sounds, Death Valley National Park beckons. Even as the already extreme temperatures are forecast to climb even higher, potentially topping records amid a major U.S. heat wave, tourists are arriving at this infamous desert landscape on the California-Nevada border.

Most visitors at this time of year make it only a short distance to any site in the park — which bills itself as the lowest, hottest and driest place on Earth — before returning to the sanctuary of an air-conditioned vehicle.

This weekend, the temperatures could climb past 130 F (54.4 C), but that likely won't deter some willing to brave the heat. Signs at hiking trails advise against venturing out after 10 a.m., though nighttime temperatures are still expected to be over 90 F (32.2 C). The hottest temperature recorded at Death Valley was 134 F (56.6 C) in July 1913, according to the park service.

Preliminary information form the park service shows at least four people have died this year from heat-related causes across the 424 national park sites. That includes a 65-year-old man from San Diego who was found dead in his vehicle at Death Valley earlier this month, according to a news release.

Other parks have long-standing warnings for hikers. At Grand Canyon National Park in Arizona, officials are cautioning people to stay off the trails for most of the day in the inner canyon, where temperatures can be 20 degrees hotter than the rim.

Death Valley National Park emphasizes self-reliance over expectations of rescue. While rangers patrol park roads and can assist motorists in distress, there's no guarantee lost tourists will get aid in time. More than 1.1 million people annually visit the desert park, which sits over a portion of the California-Nevada border west of Las Vegas. At 5,346 square miles (13,848 square kilometers), it's the largest national park in the Lower 48. About one-fifth of the visitors come in June, July and August.

Many are tempted to explore, even after the suggested cutoff times. Physical activity can make the heat even more unbearable and leave people feeling exhausted. Sunbaked rocks, sand and soil still radiate after sunset. “It does feel like the sun has gone through your skin and is getting into your bones,” said park Ranger Nichole Andler. Others mentioned feeling their eyes drying out from the hot wind sweeping through the valley.

Death Valley is a narrow, 282-foot (86-meter) basin that is below sea level but situated among high, steep mountain ranges, according to the park service's website. The bone-dry air and meager plant coverage allows sunlight to heat up the desert surface. The rocks and the soil emit all that heat in turn, which then becomes trapped in the depths of the valley.

The park's brownish hills feature signage saying “heat kills” and other messaging, such as a Stovepipe Wells sign warning travelers of the 'Savage Summer Sun.' Still, there are several awe-inspiring sites that draw tourists. Badwater Basin, made up of salt flats, is considered the lowest point in all of North America. The eye-opening 600-foot (183-meter) Ubehebe Crater dates back over 2,000 years. And Zabriskie Point is a prime sunrise viewing spot.