NPSによるとヨセミテヴァレーで27日午後に2件の崖崩れがあったようです。1ヶ所はセンチネルロックの東(4マイルトレイルを横断)、もう1ヶ所はハーフドームの北西壁。いずれもハイカーやクライマーに被害はない模様。
Two small to medium-sized rockfalls occurred in Yosemite Valley on Thursday, July 27. The first occurred at approximately 4:30 pm near the Four Mile Trail east of Sentinel rock, and consisted of a few small blocks that fell from a cliff band and rolled down a gully to the floor of Yosemite Valley. Although the rocks crossed the Four Mile Trail, no one was injured and the trail remains open. The second occurred at approximately 6:30 pm on the northwest face of Half Dome. A flake fell from low on the Northwest Face into a gully below the face, quickly breaking up into dust and small debris. Dust was visible over Half Dome for several minutes after the rockfall. At approximately 7:30 a helicopter reconaissance located the rockfall release point and determined that no climbers or hikers were injured by the rockfall. (G. Stock – 7/31/06)