Watch for solar warming in the alpine, especially on sunny slopes. Moderate winds continue to create wind slabs and cornices. Pay attention to changing conditions today!
Weather Forecast
A ridge of high pressure will maintain dry conditions today, however a NW flow may spread some cloud and snow later today and Wednesday. An inversion is also likely today. The inversion, combined with sunny breaks and solar radiation, may cause snow to become weak and unstable on solar aspects,
Snowpack Summary
Soft and hard wind slabs overlie the January 4 sun crust-surface hoar layer. This layer is down 40-60cm. The sensitivity of this layer is quite variable, however skiers have been triggering avalanches on this layer in specific terrain features. Steep solar aspects are most reactive. The mid-pack remains strong.
Avalanche Summary
Skiers have been triggering avalanches in isolated locations in the alpine and treeline, mostly on steep solar aspects. The largest of these was a size 2.5 Sa from two days ago, and a size 1.5 from Grizzly Shoulder yesterday. Isolated natural avalanches have been observed from steep start zones. Use caution on wind loaded areas on solar aspects.
Confidence
Timing or intensity of solar radiation is uncertain on Wednesday
Problems
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.
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.