A 19-year-old Petaluma woman found dead in the snow near South Lake Tahoe appeared to have taken a wrong turn on New Year's Eve and wandered through the snow a short distance before shedding her winter jacket and coming to rest behind a snow bank, authorities said Monday.
Alyssa Byrne was found dead three days later, her boot prints the only ones in the vicinity. The pattern of the footprints suggested disorientation that may have been caused by alcohol consumption, hypothermia, or both, an El Dorado County sheriff's official said.
"I don't want to speculate," sheriff's Lt. Pete Van Arnum said, though he confirmed authorities have received reports that Byrne had been drinking while in town with friends for an outdoor music festival.
He also noted that advanced hypothermia causes confusion and deteriorating cognition. Victims can become disoriented and lose judgment.
"It was subzero that night and, depending on how long she was out in the cold, that could have affected her," Van Arnum said.
Experts say it's common for those with fatal hypothermia to remove clothing shortly before death because of physiological changes that cause a spreading sense of warmth.
Byrne, a 2011 Casa Grande High School graduate, was attending the three-day SnowGlobe Music Festival at Lake Tahoe Community College when she died late New Year's Eve or early the next morning.
She had driven to Lake Tahoe the previous Saturday with three friends and was sharing a room with them at the Horizon Casino Resort in nearby Stateline.
But on New Year's Eve she got ahead of her friends in a concert crowd and suddenly disappeared around 11 p.m., telling a friend by cellphone 30 minutes later that she was taking a shuttle bus back to the hotel. They never saw her again.
For the next three days, family and friends conducted an increasingly frantic search for clues to what happened to her.
On Friday morning, a public utility worker perched atop an elevated truck peered over a four-foot snow bank and spotted her lifeless body about a half-mile from the junior college campus, authorities said.
Byrne was lying about 10 feet off Pioneer Trail, near Al Tahoe Boulevard, which leads to the college campus and runs between Pioneer Trail and Highway 50.
Authorities said long shuttle bus lines may have caused her to join others who elected to walk back to Stateline — an approximately 4-mile route that would have followed Al Tahoe Boulevard and then turned left along Pioneer Trail, headed northeast. It also is possible she walked through the campus instead of taking a bike path used by others, Van Arnum said.
But her final location indicated she turned right on Pioneer Trail, rather then left, walked along the road a ways and then climbed over a 4-foot berm of frozen snow pushed off the roadway, Van Arnum said.
"Most of the people, if they were walking on foot and if they were headed back to the Stateline area, would have been going the other direction," he said.