Tetons

The General Avalanche Hazard remains MODERATE at the Mid and Upper elevations. Two avalanche situations are possible today: First, surface slabs one to three feet in depth, which rest atop suncrusts and buried surface hoar, remain susceptible to human triggers. Yesterday skiers triggered a large slide on an east facing slope on Mount Taylor near Teton Pass and Saturday skiers remotely triggered a large slide on a Southwest facing slope outside the Grand Targhee resort. The second avalanche problem is deep slab instability, which is most problematic in areas that have a shallow, continental snowpack which can be found on sunlit aspects and recently covered cliff bands and rock outcroppings. Weak faceted snow lies beneath a supportable upper snowpack, and can give backcountry travelers a false sense of security. Saturday, two skiers triggered and were partially buried by such a slide on a Southeast aspect near The Great White Hump north of Teton Pass while they skinned up the slope for the second time. With continued cold weather the avalanche danger will increase as weak faceting moves up into the snowpack. The General Avalanche Hazard at Low elevations is LOW.

Inversions will steepen as warmer air moves over at mountain top elevations. 10,000 foot temperatures will rise to twenty degrees f. Tuesday but the valley floors will continue to be very cold. Ridgetop winds will be northerly at 10 to 15 mph. The General Avalanche Hazard will be MODERATE Tuesday. Two avalanche scenarios remain possible: First, surface slabs one to three feet in depth, which rest atop suncrusts and buried surface hoar, remain susceptible to human triggers on many aspects. The second avalanche problem is deep slab instability. Normal signs of stability such as previous tracks may only be the beginning of the weakening of the stronger surface snows. Under the current weather conditions the snowpack will become weaker and weaker and the chances of triggering a large, hard slab will increase. This condition has existed in the Greys river area to the South and Togwotee Pass to the East. With a Moderate hazard always use good stability evaluation skills and avoid open avalanche paths despite the behavior of those willing to accept higher levels of risk.