The new snow is gaining strength however previous winds have loaded lee features in the alpine. Below that the Jan 4th layer may be a "sleeping giant"
Weather Forecast
Another cool cloudy day today with light west winds, alpine temps to -10C and freezing level to 500m . Wednesday looks similar but models show precip on the way Wednesday night through to Saturday. Possibly amounting to 25 cm.
Snowpack Summary
Last week's storm produced 50cm of storm snow which is now settling and gaining strength. Soft wind slabs should be expected on lee features after mod-strong S-SW winds on the weekend. Jan 4th interface down 60-100cm and is still producing sporadic whumfing and is possible to trigger especially in less traveled areas or where snowpack is thin.
Avalanche Summary
Natural avalanche activity has tapered off with the cooling temps, however with clear breaks yesterday evidence of many large recent avalanches were observed. WIth lots of available snow to transport any increase in winds could create a more cohesive slab.
Confidence
Due to the number of field observations
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
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.