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.
‘‘We just don’t think he survived at this point,’’ Sergeant Cindi West said Monday.
Dozens of searchers were out four days ‘‘calling and calling,’’ West said. ‘‘If he survived, he wasn’t conscious enough to yell to us.’’
It snowed Thursday night and temperatures have been in the 30s and 40s around Mount Si, a steep and heavily forested 4,200-foot peak about 30 miles east of Seattle.
Searchers covered 9 square miles before the ground search was suspended Sunday. Fog on Monday prevented a helicopter search.
Ruppert was taking turns with two friends when he jumped out of a helicopter at 6,500 feet and disappeared.
The webbed wing suit allows a skydiver to glide at up to 100 miles per hour, so Ruppert could have covered a lot of ground, West said.
Friends in Florida say Ruppert had been skydiving seven or eight years and was experienced in a wing suit.
There is a record of Ruppert’s cellphone signal until he jumped or shut it off, West said. That information led to an extensive search of a quarter-square-mile area.