Matthew Greene, 39, was reported missing on July 29th.
He was supposed to meet up with friends after camping in the Sierra Nevadas, but never made it.
"At this point we just want to find him, to know what happened to him," said Greene's sister, Tiffany Minto.
A group of Greene's friends from the Lehigh Valley plan to spend next week out in California, retracing the hiker's steps.
