Up to 18 inches of new snow has fallen in the Tetons since yesterday afternoon and more is in the forecast for today. Strong southwesterly to westerly ridgetop winds has accompanied this snowfall and formed new, soft winds slabs in leeward terrain. This rapid loading event has also added weight to existing persistent slabs. At the mid and upper elevations, very dangerous avalanche conditions exist, and TRAVEL IN AVALANCHE TERRAIN IS NOT RECOMMEDED. At the lower elevations, use cautious route finding and avoid any terrain beneath higher avalanche paths.
Winds slabs have formed on slick sun crusts in sunlit terrain. On shaded slopes, they are building upon surface hoar and loose snow. These slabs, with depth of one to three feet, will be very sensitive to human triggers and could release naturally. As additional snowfall accumulates, these slabs will increase in depth and become more susceptible to failure.
Additional weight from the new snowfall has increased the likelihood of triggering persistent slab avalanches. These slides, which could be up to five feet deep, could be triggered by skiers and riders or step down from the release of a new wind slab. This threat will also increase during the day with continued loading.
