Dangerous avalanche conditions continue at the mid and upper elevations of the Teton Area. Avalanche problems include both wind slabs formed during the past weekend's storm and persistent slabs that involve deep weak layers that were buried on December 11th. These older slabs, if triggered, can be quite large and carry severe consequences. Yesterday a snowboarder was caught when an east facing slope at an elevation of 8300' failed near the ground. He was carried down the path and partially buried without injury. Smaller slides were also triggered yesterday. Cautious route finding is essential today as the deep problem is widespread and it is becoming increasingly difficult to predict which slopes may or may not fail. The best course of action is to avoid steep avalanche prone terrain. Below 7500 feet, avalanches are unlikely today except in steep isolated terrain features.
Avalanches involving weak faceted snow and crusts that formed in early December could be human triggered today. These slabs are likely to be hard and could have depths to four feet.
Winds that were from the southwest to west during Saturday's storm and from varying directions since have formed slabs on the surface of the snowpack in terrain above 8500 that is prone to wind loading. These soft slabs could be triggered today in steep terrain with depths to eighteen inches.
Cold temperatures and light winds are expected tonight into tomorrow morning. Inversions will again set up with bitter temperatures in the valleys while higher elevations start in the single digits. A weak system will move in and bring the possibility of light snow by mid-afternoon. The general avalanche danger will remain Considerable above 7500 feet in the Teton and Southwest Trails area and Moderate in the Togwotee Pass area. It will be Low below that elevation. The problem is the same in all locations. Although smaller wind slabs could still be triggered, the primary concern is for failures to occur deeper in the snowpack. These slides could be hard slabs and very large in the Teton and Southwest trails areas where they will also be more sensitive and could be triggered remotely. Although the Togwotee pass area has a similar problem, less loading has occurred there so the slides have not been as sensitive or as large. At lower elevations, the snowpack structure is poor but depths remain low and activity is limited to isolated very steep terrain features. The travel advise is to simply avoid steep, known avalanche paths and enjoy the great conditions that are present in lower angle terrain. Under these conditions, snowpack evaluation can provide insights into what the snowpack layering is like and in knowing where future weaknesses lie but be cautious in allowing any test results to green light any steep slopes.
