Yesterday afternoon, strong southwesterly to westerly ridgetop winds continued to build wind slabs in leeward terrain. Skiers and riders could trigger these small to large slabs in steep, wind loaded starting zones above 8,500 feet. The release of one of these slabs could also initiate a large to very large deep persistent slab. Be on the lookout for unusual patterns of wind loading and avoid steep terrain with significant deposits of drifted snow, especially if surfaces are hard and drummy. Backcountry travelers might be able to trigger an isolated pocket of wind slab in very steep terrain below 8,500 feet.
On steep, wind loaded slopes above 8,500 feet, backcountry travelers could trigger dense wind slabs to depths up to 30 inches. These slabs reside above a variety of old snow surfaces which include surface hoar, near surface facets and sun crusts. Some potential may remain for skiers and riders to trigger similar slides up to 12 inches deep below 8,500 feet.
Above 8,500 feet, skiers and riders may still be able to trigger persistent deep slabs ranging in depth from two to four feet. These dangerous avalanches are more susceptible to failure on northwesterly through northeasterly aspects and could step down from the release of a wind slab. Being caught in one of these slides could easily result in a fatality.
( Discussion is generated from the previous day's afternoon forecast. )Ridgetop winds will decrease overnight and back to the south before increasing in the afternoon and veering back to the west. Light snowfall will continue tonight before the next shortwave moves into the area late in the day on Sunday. Overnight lows in the mountains will be near 10 degrees before rising into the mid-teens in the afternoon.On Sunday, the general avalanche hazard is expected to remain Considerable in the higher elevations of the Tetons and Southwest Trails area. Up there, backcountry travelers could trigger winds slabs with depths ranging from one to three feet in steep, wind loaded starting zones. On Togwotee Pass, where winds were lighter, the general avalanche hazard is expected to remain Moderate, and human triggered wind slabs will continue to be possible. Avoid steep terrain with significant deposits of drifted snow, especially if surfaces are hard and drummy.In all three forecast zones, skiers and riders still have some potential of triggering persistent deep slabs with depths of three to five feet. These dangerous avalanches are more susceptible to failure on northwesterly through northeasterly aspects above 8,500 feet and could step down from the release of a wind slab. Being caught in one of these slides could easily have fatal consequences.
