SEATTLE — The search for a skydiver wearing a wing suit in the Cascade foothills will continue by helicopter as the weather allows, but officials said they do not expect to find him alive.

No one saw a parachute Thursday, and if Kurt Ruppert, 29, of Lake City, Fla., survived the jump and was caught in a tree or lost in the forest, he probably died of hypothermia, a King County sheriff’s sergeant said.