This avalanche occurred sometime on Thursday and the information is through second hand knowledge.  A group of six snowmobilers were riding in the Humpy Peak area when one rider was high marking and triggered a slide that caught other members of the group that were at the bottom of the slope.  The rider who triggered the slide was able to stay on top through swimming motions while at least three people were partially buried. No injuries were reported, but machines were badly damaged and had to be towed out.  

 The Humpy Creek area has been very active with numerous human triggered avalanches and this exact slide path was triggered back on 1/23/11 and failed on surface hoar that formed in early January.  Pictures are posted of the first slide in the Uinta avalanche list.  This recent occurrence also appears to have failed on the January 8 surface hoar, but this time the starting zone was higher on the slope.  As Craig pointed out this could have been a much larger and more tragic outcome had this slope not released previously, as the debris would likely have been much deeper.