Travel in avalanche terrain is not recommended today. Above 8,500 feet dense slabs may release naturally and will be easily triggered by humans. Avalanches could be in the form of wind slabs or larger persistent slabs. Avalanches originating in the upper elevations hold the potential to run long distances and cross into the lower elevations. It will be critical to know the terrain above you and plan your travel accordingly.
New snowfall, strong winds and warming temperatures over the past 24 hrs have created upside down conditions on leeward aspects above 8,500 feet. Additional snowfall and more importantly strong winds will add to this problem today. Slabs will range from 1-2 feet in depth. Expect more recently formed slabs to release naturally and be very sensitive to human triggers.
Weak layers of snow now buried between 1-4 feet deep have been stressed and tested over the last four days. Whether or not these layers have reached the tipping point is not clear. Due to the severe consequences of involvement in an avalanche of these depths, the best approach to this uncertainty is avoidance. These avalanches could be initiated by a newer slab, by the weight of a single person or require larger triggers such as a snowmobile.
( Discussion is generated from the previous day's afternoon forecast. )A Winter Storm Warning issued by the NWS will remain in effect until 11pm tonight. By morning expect another 4-6” of snow in the Tetons, 2-4” on Togwotee and 4-6” in the Grey’s River. Light snowfall will continue tomorrow, with 24 hours totals of 8-10” in the Tetons, 3-6” on Togwotee and 6-8” in the Grey’s River. Winds will be out of the west at 25-35 mph. Temperatures will remain mild, with ridgetops in the low twenties and valley locations hovering around the freezing mark overnight and into the afternoon tomorrow.While precipitation will ease slightly, loading will continue overnight and through the day tomorrow. Along with mild temperatures, this will likely keep the avalanche danger in the high range in upper elevations and considerable in the mid and lower elevations. The snowpack in all three forecast areas has undergone dramatic change. Weak interfaces within the recent snow as well as deeper weak layers simply need time to adjust.
