PRELIMINARY: Two snowmobilers were riding in Haskins Creek, west of Battle Pass in the Sierra Madre range. They triggered an avalanche while riding on the lower portion of an open, east-facing slope. The avalanche broke two to eight feet deep and very wide. Both riders were caught. Rider 1 rode out of the moving debris and turned to see that Rider 2 was partially buried-critical, with his feet in the air and head below the debris. Rider 1 dug his partner free and performed CPR, but Rider 2 did not survive.
Observation on Eastern Wyoming Avalanche Information Exchange