The avalanche cycle has tapered off but alpine conditions have not changed significantly. A melt freeze crust has stabilized conditions below treeline.
Weather Forecast
Mild and dry conditions will continue on Friday. Around 10 cm of snow will start falling on Friday night with light west winds through Saturday. Cold air moves into the area on Saturday night bringing clear crisp temperatures on Sunday.
Snowpack Summary
There is a melt freeze crust at treeline to valley bottom. The crust weakens into treeline. In the alpine, heavier snow sits over a persistent weak layer dating to Dec 20th.
Avalanche Summary
The avalanche activity has slowed with the cooler temperatures. Several slab avalanches to size 2.5 from the past 24 hrs were observed on easterly aspects around 2400 m. Previous loose wet avalanches were numerous on lower elevation westerly aspects and pin wheeling was observed up to 2300 m.
Confidence
Timing, track, or intensity of incoming weather system is uncertain on Saturday
Problems
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.