Some storm snow and winds are expected Friday into Saturday. Monitor loading patterns after the storm as surface instabilities will exist until the snow has stabilized.
Weather Forecast
A warm front followed by a cold front may pass through Friday into Saturday. Severe SW winds at 3000m and 50km/hr winds at 1500m may be here Friday am followed by 15cm of snow starting late Friday afternoon into Saturday am. Saturday and Sunday, winds will settle, temperatures will be seasonal, light flurries, and variable clouds.
Snowpack Summary
Variable windslabs exist in the alpine and treeline locations. They are bonding well to the previous surfaces. Many spots have been stripped of Saturday's storm snow revealing previous sustrugi and windslab surfaces with windpressed pockets in between. Weak facets dominate low elevations. Solid midpack bridges basal facets treeline and alpine.
Avalanche Summary
Thursday's patrol into Portal creek from Marmot basin revealed no new avalanches. No Patrol on Wednesday. Tuesday observed only a couple size 1.5 very steep loose avalanches @ 2600m appearing to be solar triggered. One size 2 thin slab was noted at 2700m E aspect on a very steep unsupported feature. They appear to be stopping where angle changes.
Confidence
Timing, track, or intensity of incoming weather system is uncertain on Friday
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.