The main stability concern today will once again be wind slabs on lee aspects (SE-NW).  These will be possible to trigger in specific locations up to 1 foot deep.  Cross loaded gullies, the lee side of terrain features and  lee of ridge lines will be the areas where windslabs exist.  Windslabs may exist further down from ridge lines than you may expect due to the strength of the latest wind event.

On 12/24 windslabs were found to be 4-6 inches deep and stubborn to triggers.  Depth and sensitivity of recent windslabs may vary from place to place. Deeper windslabs likely exist in isolated locations.  Pay attention to where winds have deposited slabs and investigate the depth and sensitivity in the area that you choose to travel to asses the hazard.

The hazard for this problem may increase during the day if new snow and wind arrives earlier and heavier than forecasted.  By Monday morning new snow and strong wind will likely move the avalanche hazard to Considerable.

Faceted snow near the base of the snowpack has been identified in all three forecast zones. In most locations above brush line, faceted snow is capped by pencil-knife hard wind affected snow.  This has created a strong bridging affect making a person or machines weight unlikely to directly affect these layers. 

Our area received 3-4 inches of snow water equivalent over a 5 day period beginning 12/11.  This put significant stress on these weak layers.  Natural avalanches did occur, but activity was not widespread and natural avalanches were mostly confined to the storm snow.  This points to the strength of the wind hardened snow overlying the weak facets at the base of our snowpack. 

It has been eight days since the last significant snowfall event, and stability tests that directly target these layers have not been producing significant results since.  One exception was an interior location  just north of our continental forecast zone where propagation in stability tests still existed on 12/18.

Persistent weak layers are tricky to assess and are notorious for surprising people.  As long as temperatures remain cold and our snowpack is thin, these weak layers will continue to lose strength.  It is likely that facets will reactivate in the future when stress is being applied through dramatic changes in weather such as: significant snow accumulation, rapid warming and wind loading.  Maintaining safe travel protocols such as skiing one at a time and avoiding traveling in or above terrain traps will increase your safety margin.  

 The most likely areas to trigger a persistent slab avalanche would be in steep terrain that was protected from previous strong winds that have occurred this season. This could be below brushline or in areas of terrain that are typically spared from outflows.  The Continental zone remains suspect as this area has a weaker snowpack and generally receives less wind, which would decrease the bridging affect mentioned above.