Kirk Thomas Olsen, a 61-year-old man, has been missing in Yosemite National Park since August 27 after planning a backpacking trip to the Ostrander Lake area from August 23 to 27. Park officials have reported that he is 6 feet tall, weighs 190 pounds, has blonde hair, blue eyes, and a fair complexion. Authorities are urging anyone who was in the Ostrander Lake area during these dates to come forward, regardless of whether they believe they saw him. The hike to Ostrander Lake is strenuous, involving significant elevation gain and spanning over 11 miles. Park rangers are requesting tips through their investigative services tip line at 888-653-0009 or via email at nps_isb@nps.gov. This incident follows previous cases where hikers reported missing in Yosemite were found safely after public assistance was sought.