A 26-year-old California woman fell 600 feet to her death Sunday while descending Yosemite's famous Half Dome, the National Park Service said Monday.
Hayley LaFlamme, of San Ramon in the Bay Area, was pronounced dead at the scene shortly after park rangers received a 911 call around noon reporting the fall of a hiker from the steps and cable system up the steep granite face.
The park service said that LaFlamme appeared to have slipped while climbing back down, accompanied by three friends.
"A severe lightning, thunder, and rainstorm was present in the area of Half Dome for several hours in the morning and early afternoon yesterday," the park service said in a statement. "This type of weather can make for hazardous trail conditions and the granite slopes become very slick."
Signs warn Half Dome hikers against using the cables during rain and lightning but the trail does not officially close, park spokeswoman Kari Cobb said, according to the Los Angeles Times.
LaFlamme's death is the 14th at the park this year, well above the 5-6 averaged in recent years through July.
The last hiker to die on Half Dome was a visitor, also from San Ramon, in June 2009, the park service said.
The death comes two weeks after three visitors plunged over a Yosemite waterfall . While their bodies have not been recovered, they are presumed dead. It is believed the bodies are trapped under rocks.
The search for their bodies was scaled back last week. Rangers hope to be able to find the bodies in autumn when the water recedes.
The Associated Press contributed to this report.