A cooler day forecasted for tomorrow with overcast skies and flurries. If the sun does burn through, we may see isolated loose wet avalanches in solar terrain.
Weather Forecast
For Thursday, the forecast calls for mainly cloudy skies with flurries (5-10 cm) with light to moderate East wind flipping back to SW once the bulk of the snow arrives. Freezing levels will rise to only 1800 m tomorrow and return to surface overnight.
Snowpack Summary
3-5 cm of fresh snow at upper elevations with some wind effect and thin wind slabs in isolated areas. Various types of temperature crusts or moist snow found on solar aspects and found on all aspects below 1900 m. The March 15 suncrust is down 25-50 cm on solar aspects and still is a concern for skier triggering.
Avalanche Summary
Two cornice triggered avalanches size 2-2.5 in Sunshine region on a NE and S aspect, occurred late in the day yesterday. Also evidence of loose wet snow avalanches up to size 2 on solar aspects over the past few days. No natural activity noted today at the time of writing the bulletin.
Confidence
Intensity of incoming weather systems is uncertain
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.