Northwest Inland

Expect avalanche danger to increase in areas that receive heavy loading from new snow and wind. Stick to mellow terrain and be extra cautious on Boxing Day.

Moderate - Due to the number and quality of field observations

SUNDAY NIGHT: Flurries with accumulations of 5-10 cm with strong to extreme southwest winds.MONDAY: Stormy with accumulations of 10-20 cm, extreme southwest winds, temperatures around -10C.TUESDAY: Flurries with accumulations of 5 cm, strong west winds, temperatures around -8C.WEDNESDAY: Cloudy with isolated flurries, strong southwest winds, temperatures around -8C.

Persistent slabs have been very touchy in areas with thin snowpacks. Over the past few days, several size 1.5-2 avalanches have been remotely triggered by skiers in the northern part of the region, and a size 3 persistent slab was triggered with explosives on Saturday. These avalanches have released on weak facets near the ground in steep shallow start zones. Remote triggering is a sign of a serious weakness deep in the snowpack and indicates that persistent slab avalanches may be triggered with very light loads.On Monday, the new snow will form reactive wind slabs. Wind slabs may be extra touchy in areas where they are burying a newly formed surface hoar layer. The additional load of the new snow will also make it possible to trigger weak layers deeper in the snowpack and produce large persistent slab avalanches.

Expect 15-30 cm of fresh storm snow by Monday afternoon, with extreme winds forming extra deep pockets in the lee of ridgetops. The storm snow will likely bury a new layer of surface hoar that formed in sheltered areas, making wide propagations possible. A weak interface that formed during the early December cold snap can be found buried about 50 cm deep. The layer consists of weak faceted (sugary) snow, and preserved surface hoar in sheltered areas. The snow above this interface likely remains poorly bonded. The snowpack is still shallow throughout the region and widespread faceting of the entire snowpack is likely in most areas. A thick rain crust that formed in early November is probably near the bottom of the snowpack and is likely surrounded by sugary facets. Basal facets and depth hoar (more sugary crystals) right at the bottom of the snowpack are reportedly widespread.