The body of Petaluma resident Alyssa Byrne was found this morning in South Lake Tahoe.In a Friday morning press conference, Douglas County Undersheriff Paul Howell said a utility worker found Byrne's body behind a high snow bank 10 feet off Pioneer Trail between Al Tahoe and Black Bart Avenue about 8:30 a.m. Police said her body was just off the roadway about 1 mile west of Lake Tahoe Community College, where SnowGlobe was held. Her body looked like it had been there for a couple days, he said.According to the National Weather Service, the temperature dropped to 3 degrees Jan. …