Tetons

Yesterday morning, the higher elevations in the Tetons received two to four inches of new snow. In areas where drifting occurred, some cracking and whumpfing was observed. These observations are indicative of the behavior of persistent weak layers that are in the initial stages of being loaded. Be aware of these shallow instabilities in isolated terrain features.

A zonal flow extends well west into the Eastern Pacific. A series of short wave troughs and jet streaks in this flow are poised to bring pulses of moisture into Western Wyoming. Periods of light snowfall are expected overnight and through Monday. Accumulations of four to six inches are possible. Temperatures will mostly remain in the 20s in the mountains and could rise above freezing in the valleys during the day. West to southwest winds will average 20 to 30 with gusts to 40 miles per hour.The general avalanche hazard will begin on the increase as strong winds begin to build shallow pockets of new soft slab upon slick and weak old snow surfaces. Isolated pockets of slab could build to depths of six to 12 inches on leeward aspects in upper elevation starting zones. The general avalanche hazard is expected to be LOW but increasing. Monitor conditions and be aware of the increasing hazard. These shallow new slabs are likely to be very sensitive to human triggers if significant loading occurs. Be prepared to alter plans if forecast snowfall amounts are exceeded.