Riders and skiers have the potential to trigger recently formed slabs in steep avalanche terrain today at the mid and high elevations. These slabs lie upon slick sliding surfaces and weak snow layers. Once initiated these avalanches could fail to deeper weaknesses in the snowpack and in shallow areas slides could fail to the ground. At low elevations, small slides could be triggered in isolated areas. Slopes with terrain consequences should be avoided. Yesterday skiers remotely triggered three slides in Grand Teton National Park on Maverick.
West to northwest winds and recent snowfall have formed surface slabs on leeward aspects. These slabs could have depths to two feet and will be most sensitive at higher elevations where they lie upon a variety of snow surfaces including sun and wind crusts.
The triggering of slabs that lie upon persistent layers of weak snow will be most likely at the mid and low elevations where new snow lies upon layers of surface hoar and in many areas, a generally faceted snowpack. At high elevations the persistent weaknesses are deeper in the snowpack, less likely to trigger and therefore harder to predict. If triggered, however these hard slabs would carry severe consequences.
A series of arctic cold fronts will move south from Canada and spread across Western Wyoming through much of the week. On Sunday skies will be mostly cloudy with a slight chance for snow showers over the mountains. Temperatures will remain in the single digits and teens. Winds will be light from the west to southwest at 5 to 10 miles per hour.In the Teton Range the general avalanche hazard is expected to be MODERATE. Surface slabs 12 to 30 inches in depth could be human triggered and may have some potential to step down to deeply buried layers of faceted snow. The general avalanche hazard in the Continental Divide/Togwotee Pass and the Southwest Trails/ Greys River areas is expected to be CONSIDERABLE. In those areas large human triggered persistent slabs and surface slabs are much more likely to step down to the ground.
