Buried surface hoar exists 1.5-3 feet deep in the intermountain and continental zones on all aspects above 2500′.  A significant natural avalanche cycle occurred at this interface during the 1/23-25 storm (see avalanche activity section) .  This layer has been found to be reactive in stability test as recently as 1/28, although results are becoming more stubborn and the faceted grain in question is rounding and becoming mixed with rounds (stronger snow).  The depth of this weak layer is variable depending upon the area you choose to travel.  Where it is closer to the surface  (16-20 inches) human triggered avalanches are more likely.  Where buried surface hoar is 3 feet deep or more the likelihood is less, although if triggered, wide propagations could be expected.

Signs of instability may not exist even when dangerous conditions are present.  Digging snowpits is the most effective way to identify where this layer is present and its sensitivity.   Although, this can be a difficult assessment tool due to spatial variability (conditions that vary from place to place) and results that may be confusing or misleading.  This layer is becoming more subtle and could easily be missed.

Weak snow exists near the base of our snowpack in all three climate zones.  Recent heavy snowfall and rising temperatures has increased the stress upon this weak snow.   The likelihood of deep human triggered avalanches has gone from unlikely to possible.  This layer will be difficult to directly affect by a person or machine but a persistent slab avalanche (see problem 1)  may be able to step down to deep layers in our snowpack.  DOT avalanche mitigation efforts did just this on the buttress to the east of nicks(see avalanche activity section), showing that it is still possible for deep layers to produce avalanches.  The most likely areas to affect deep instabilities would be in steep rocky areas where the snowpack is thin in the continental zone.