Abundant new snow is rapidly loading steep slopes and creating unstable conditions. Soft surface slabs will be forming and gaining size as the day progresses. These slabs are likely to be very sensitive to human triggers in steep terrain and could release naturally. Deep persistent slab avalanches pose a serious threat to humans in steep avalanche prone terrain that faces north above an elevation of 9,000 feet.
Soft surface slabs formed by southwest, northwest and east winds could be human triggered or release naturally on steep avalanche prone slopes. These slabs could be up to two feet in depth.
Persistent deep slabs with depths to six feet could be human triggered in steep avalanche prone terrain that faces north above an elevation of 9,000 feet. New snow is rapidly loading these dangerous slabs and is increasing the potential for these deep slabs to be human triggered. The consequences of triggering one of these destructive slabs are likely to be fatal.
( Discussion is generated from the previous day's afternoon forecast. )Moderate to heavy snowfall is expected late tonight through Wednesday night in the Salt River Range, Wyoming Range and over the mountainous areas of southeast Idaho. Lesser amounts are forecast for the Teton and Togwotee Pass areas. Total snowfall accumulations by Thursday morning are expected to be 10 to 16 inches in the Greys River area and 5 to 10 inches in the Teton and Togwotee Pass areas. Temperatures will remain in the single digits above and below zero. Southwest winds will veer to the northeast during the day and be light with average speeds of 10 to 20 miles per hour. The general avalanche hazard is expected to be MODERATE and increasing, especially in the Greys River forecast area where it could increase to CONSIDERABLE. Soft surface slabs up to two feet in depth and loose snow sluffs could be human triggered in steep terrain. Deep persistent slabs with depths to six feet could be human triggered in steep north facing avalanche prone terrain above an elevation of 9,000 feet. These dangerous deep slabs are more susceptible to heavy triggers like snow machines.
