Tetons

The persistent slab problem continues to be a threat to backcountry travelers. Yesterday, a soft slab was triggered by a large group of approximately 15 skiers at the Jackson Hole Mountain Resort in an area that had seen several rounds of explosive mitigation including yesterday morning. The relatively small slide(R-1), caught many people and partially buried 5, two of them critically, meaning head covered with part of their body or equipment exposed. Similar events could occur today in the backcountry and humans also have the potential to trigger recently formed soft slabs or loose snow sloughs. Snowpack evaluation may not provide the information needed to determine slope stability, therefore cautious route finding and decision making is essential. Avalanches are unlikely below 7500 feet except in isolated pockets in steep loaded gullies.

Cold air will keep temperatures in the single digits at the upper elevations overnight and highs in the low teens tomorrow. Mild inversions are again expected in the morning at the low elevations, where highs in the mid-twenties are possible in the afternoon. Moisture from a weak disturbance over Utah will provide clouds and the chance for occasional flurries or perhaps an inch or two of accumulation tonight through Monday. The general avalanche danger will be Moderate at the mid and upper elevations. The persistent slab problem involving faceted snow will continue tomorrow and into the foreseeable future. As the snowpack adjusts to recent loading these slabs will slowly decrease in likelihood of triggering, meaning they will be less sensitive. Make no mistake that this does not indicate that slopes are stable. They will simply be harder to predict and may fail after a slope has been tracked several times once a weak spot on the slope is hit or to larger loads such as groups or snow machines. Avalanches at low elevations remain unlikely due to relatively shallow snow depths, and potential activity is limited to wind loaded steep gullies.