It was a dream fulfilled, followed by a nightmare. Jonathan Rohloff and his daughter Grace had hiked thousands of miles together, and after securing a permit to hike Yosemite National Park's Half Dome trail, made it to the top on the afternoon of July 13. Storms had been forecast, but the skies had been clear—but as they took photos at the top, thunder sounded.

Rohloff tells they knew they had to quickly make their way down, beginning with the 400-foot stretch of trail that reaches the summit and is supported by two metal cables. Rohloff says that based on their experience, he and his daughter, an Arizona State University student, could have made it down quickly ahead of the rain. But other hikers were ahead of them and moving painstakingly; trying to pass them as they were all attempting to flee seemed rude, he says.

The rain-slicked granite made it difficult to get traction, a situation exacerbated, he says, by Grace's new hiking shoes, which the reports the 20-year-old bought in preparation for the hike. She complained they felt slippery, and he urged her to continue to go slowly. But with about 75% of the cables behind them, both her feet went out and she slid as many as 300 feet.

"It happened so fast. I tried to reach my hand up, but she was already gone," Rohloff says. He called 911, then prayed and yelled to his daughter in case she could hear him: "Grace, I'm here.

I'm not going to leave you. If you can hear my voice, give me a sign. I love you.

" Three hours later, .