Park officials did not say where or when the accident happened but a witness said it was at a campground near Half Dome Village.
"It was very close to my tent. It would be just two tents over," the witness said.
He and his wife were not there when the tree came crashing down. The two were returning from getting coffee - only to return and come face-to-face with park rangers stopping them from going in.
"There was a fire truck and an ambulance and there was a body being put into the ambulance, and I looked at the feet hoping to see them moving and I didn't see that," he explained.
The Central Valley man says when they first arrived Friday for their weekend stay, a park staff employee told him the storm expected to hit.
"She mentioned there was a big storm coming, and it might be a big one and we could be evacuated," he said. "That was a possibility, she did not know that for a fact at all."
The man who escaped danger feels for the victim's family.
"I love everyone on this planet," he said. "And I feel horrible when things like this happen."
Officials did say that roads leading to Half Dome and Upper Pines have been closed off until 12:00 p.m. Monday because of tree fall danger due to high winds and snow.
The identity of the woman has not been released.