Conditions are prime for creating fresh wind slabs right now, and we have had quite a bit of wind over the last week that have created wind slabs on multiple aspects. Winds have shifted from S to SW and W and to NW.  Wind slabs of varying thickness and strength can be found on upper elevation terrain on E, N and W terrain.  Some of these may be overlying buried weak layers. 

Watch for visual clues such as ripples, pillows or changes in texture of the snow pack as you travel through the wind affected upper elevations.   In addition, the amount of wind transport is allowing a dense and surprisingly deep snow pack to build quickly in the upper elevations. 

As the next storm enters our area later today expect to see prefrontal winds increasing into the lower to mid 20mph range.  With a lot of light density snow available on the ground right now, additional wind loading should be expected on all leeward terrain.

Variability is the name of the game right now in our local snow pack.  This variability runs the spectrum from solid and consolidated snow to weak and unconsolidated with extremely weak layers waiting for a trigger. The problems are also varied creating a complex forecasting and decision making process.  In a nutshell:

•  Buried surface hoar exists in a growing and strengthening snow pack.  The layer of buried surface hoar that we have been watching is now 2-3 feet down in the snow pack below a slab that is gaining density and depth but not getting stronger.  So far the weight of the new snow has not been enough to tip the scale on a widespread natural avalanche cycle.  This layer is also mostly confined to shady, wind protected areas.
• Basal Facets-leftover snow from early season storms and the cold start that we had to December.  Our entire snow pack is resting on a pile of kitty litter in some places creating the whumps and collapses that are still being reported as this layer fails when weighted by a skier or snowmobile. Shallow rocky areas and north facing terrain are still harboring alarming pockets of loose faceted snow.
• Wind slabs ranging in thickness and sensitivity near the ridge tops.
• Incremental loading from a series of small storms that have not provided the weight to trigger the weak layers in a natural avalanche cycle or squash them down enough to take them out of the equation.

 Snow pros and savvy backcountry travelers have a healthy respect for this kind of a snow pack scenario.  A great analogy is that we are building a house of cards right now and it is getting progressively taller and more wobbly.  As we add either ourselves or additional snow weight from storms or wind we know the house of cards is going to fall.  Roulette might be an overstatement but this level of uncertainty in a growing snow pack is enough to keep experienced recreationist out of steep terrain right now. 

If triggered either of our current weak layers have the potential to spread out or propagate over large distances.  Even a shallow avalanche may have the ability to step down into the deeper layers below.  Your best and safest bet right now is to avoid protected slopes steep enough to produce avalanches.  This lingering problem won't go away until we have enough snow load to crush the weak layers or trigger a natural cycle.

Saw Propagation Test Video with impressive failure in Buried Surface Hoar Layer 12/20/18