Above 7,500 feet, backcountry travelers could trigger wind slabs on a variety of aspects. The possibility remains for skiers and riders to trigger a deep persistent slab on mostly shaded slopes above 9,000 feet. Evaluate the snowpack carefully, and identify terrain features where these two avalanche problems could exist. With the exception of small, isolated pockets in very steep terrain, human triggered avalanches are unlikely below 7,500 feet.
Southwesterly, westerly and northeasterly ridgetop winds have formed small to large wind slabs on a variety of aspects above 9,000 feet. Skiers and riders venturing into steep, wind-loaded terrain could trigger these slabs to depths of three feet.
Although becoming less likely, persistent deep slabs remain a concern in avalanche prone terrain on northwesterly to northeasterly aspects above 9,000 feet. A single skier or rider might still be able to trigger one of these destructive avalanches, which could have depths up to six feet. Large triggers, such as snowmobiles or groups of people, are even more likely to impact the persistent weaknesses near the base of the snowpack. Previous tracks are not an indication of stability.
( Discussion is generated from the previous day's afternoon forecast. )The region is in store for another bitterly cold night with temperatures dropping to near negative 20 in the valleys and around negative 10 in the mountains. As cloud cover increases during the day, inverted conditions will break down, and temperatures will climb into the low teens at the higher elevations and high teens in the lower elevations. Snowfall will begin to develop Saturday evening as a strong Pacific storm system starts to impact the region. Westerly ridgetop winds will back to the southwest at 10 to 20 miles per hour.The general avalanche hazard is expected to be MODERATE throughout the three forecast areas on Saturday. Persistent deep slabs will continue to be a threat on shaded and partially shaded slopes above 9,000 feet. The persistent weaknesses near the base of the snowpack will be most easily impacted in the shallower snowpack of the Togwotee Pass forecast zone. Conversely, the deepest snowpack is found in the Tetons, and the chance of triggering one of these slides is unlikely, but the consequences would be greater. The Greys River area lies somewhere in the middle in terms of snow depth. That area also recently experienced a significant loading event, and the likelihood of triggering a deep persistent slab will remain possible. Skies and riders could also trigger recently developed wind slabs in steep, wind-loaded avalanche terrain. These slabs could be up to three feet deep in the Greys River forecast zone, and generally around a foot or less in the Teton and Togwotee Pass areas.
