A group of six motorcyclists riding through a portion of Death Valley National Park experienced a lethal emergency Saturday amid record-breaking heat. One member of the group died from heat exposure and another was transported to Las Vegas and hospitalized with “severe heat illness,” while the others were treated at the scene, KLAS reports. Emergency medical flight helicopters couldn’t respond because they generally can’t safely operate in temperatures above 120 degrees Fahrenheit, ABC 7 reports. On Saturday and Sunday Death Valley hit 128 degrees Fahrenheit, beating the previous record high t…