(Portland, OR) -- The search is ongoing for a hiker who's gotten lost above Horsetail Falls. The Multnomah County Sheriff's Office says volunteer search organizations will join with deputies this morning in the effort to locate 33-year-old Jessica Wheeler of Wasco. Wheeler was reported lost around 6:40 yesterday evening. She set out on her hiking trip Monday with her dog. Crews are reported to be heading toward Nesmith Point this morning.