Tricky conditions out there right now with newly buried skier triggerable slabs being found at treeline and above. Conservative terrain selection is key. Merry Christmas!!!
Confidence
High - Due to the quality of field observations on Saturday
Weather Forecast
LIght snow and seasonal temperatures will continue through to the 26th. Winds are forecast to remain light out of the NE but looking down the road, winds and temperatures are looking like they will increase into the strong range out of the SW on the 27th.
Avalanche Summary
Conditions were somewhat obscured on Saturday but we were able to see a few loose dry avalanches up to sz 2 that ran into skiable terrain. We suspect that there are some new slab avalanche occuring in alpine areas but we were unable to confirm this due to the visibility.
Snowpack Summary
An additional 10cm of snow fell overnight on the 23rd giving us up to 20cm of snow over the past 48hrs at treeline. Lower elevations saw about half that amount. This new snow fell under the influence of light winds and as a result, has made it tougher to locate the previous windslabs that formed earlier in the week. Over the past week the forecasting team has been easily able to trigger the now hidden windslabs that were failing on a layer of facets from the cold temperatures earlier in december. These windslabs are being encountered in open alpine terrain as well as in specific features at treeline such as gullies and cross-loaded features. Conservative terrain selection is important at this time.
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.
Loose Dry
Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.