At all elevations strong winds are creating areas of drifting snow and reduced visibility. This drifting is rapidly loading leeward aspects and increasing the avalanche hazard. Fresh wind slabs will be forming on crusts and wind packed snow surfaces. These wind slabs will become larger and more sensitive to human triggers during the day. Evaluate the snow and terrain carefully and monitor conditions for increasing hazard.
Strong north to northeast winds are creating new wind slabs on leeward aspects. These slabs could build to depths of 1 to 2 feet at the higher elevations and form pockets 6 to 18 inches deep at the lower elevations. These slabs could be triggered by backcountry travelers and may release naturally in some upper elevations avalanche starting zones.
A deep slab avalanche was observed to have occurred on a northwest aspect of Palisades Peak in the Snake River Range yesterday morning. Prior to that event the most recent deep slab avalanche in our forecast region occurred on a northeast aspect of Mt. Taylor on January 19. Deep persistent slab avalanches 4 to 7 feet in depth are unlikely except in isolated locations. They could be triggered by a snowmachine that crosses a thin area of a persistent slab or by the failure of a large cornice.
Dry conditions are expected tonight through most of Tuesday. Skies are to be mostly clear and temperatures will be cold. Expect sub zero temperatures at all elevations in the morning with highs near ten at the upper elevations and near twenty at the lower elevations. Winds are to be out of the northeast overnight, then backing to the northwest with five to fifteen mile per hour averages during the day. The general avalanche hazard will be Moderate on Tuesday. Wind slabs formed today could be triggered in loaded areas with depths to eighteen inches. These slabs will gain some strength overnight but could still be triggered particularly in unsupported slopes above cliff bands and in steep chutes where a wind drifted pocket may not be apparent from the top but could release mid slope. A remote chance continues for large triggers to trigger deep slab instabilities, particularly in steep known paths such as the east face of Lava Mountain that has not slid yet this year.
