Two days of dry, warm weather following significant but consistent loading through the month of February has resulted in snowpack that has gained considerable strength. Surface slabs formed by wind and snow could still be triggered above 8000 feet. The potential also continues to trigger deep hard slabs within the snowpack. Avalanches are not expected at lower elevations today except in isolated pockets.
Strong west to northwest winds have formed wind slabs on leeward slopes at all elevations. These slabs could be triggered with depths up to three feet and once triggered could pull out deeper layers of old snow. The liklihood of triggering these slabs could increase this afternoon if significant warming and sunlight occur before the next storm arrives.
Weak layers of faceted snow persist deep within the snowpack. Failure of these layers will produce very large avalanches with depths up to six feet. These dangerous slabs have become harder to trigger and therefore it is harder to predict which slopes may fail. Larger triggers such a snowmachine or multiple snowmachines on a slope may be needed to cause failure, however, once triggered these slabs are likely to carry severe consequences or death.
( Discussion is generated from the previous day's afternoon forecast. )Another storm is on track to impact the area late on Thursday. During the day, expect increasing clouds and developing snow showers. Snow may be mixed with rain at the lower elevations. High temperatures in the mountains are to be in the upper twenties. West winds are to have average speeds near twenty miles per hour in the morning, increasing to thirty miles per hour by the afternoon.The general avalanche hazard will be Moderate in the Teton and Southwest Trails areas. In the Tetons, wind slabs could be triggered with depths to three feet in very steep and aggressive terrain. Similar events could also be triggered in the Southwest Trails area where the chance also continues for larger loads such as snowmachines to trigger old dangerous hard slabs with depths to six feet. In the Togwotee Pass area, the hazard remains Considerable. Avalanches will be easier to trigger in a shallower snowpack that developed very poor structure during dry periods early in the season. Human triggered avalanches to five feet are possible on a variety of aspects.
