Southeast Mountains

Our tricky snowpack has the potential to produce dangerous avalanches with little or no warning signs, such as this remotely triggered avalanche that snapped trees yesterday, or this destructive avalanche on Mt. Baldy a few days ago.   Though signs of instability are decreasing, our fragile weak layers are still struggling underneath slabs that are several feet thick or more, on all aspects and elevations.  You are most likely to trigger an avalanche in terrain where slabs are thinner from wind effects or a dirth in January snow totals.   Bring an acute sense of distrust into the backcountry.  

Our loading period and High danger ended last Thursday, and the likelihood of triggering a persistent slab is slowwwwwly decreasing now. We continue to see remote triggered avalanches daily, and significant natural activity continued through at least Saturday in the Elk Mountains.   Why is the avalanche danger taking longer to decrease than what we usually see? 

• Our weak layers are more fragile than what we often see.  The longer the drought, and the shallower the snowpack, the worse a weak layer becomes.  Our December drought on our shallow snowpack was a painfully long one, which means the weak layers grew larger and weaker.  Furthermore, wind events and early-season avalanche cycles kept the snowpack even shallower on some slopes going into this drought, even in our deeper zone (Northwest Mountains).  
• Our weak layers are more widespread than usual.  If the drought had happened in November, the weak layers would have melted back on sunny aspects.  That's not the case with our current setup.  The only slopes that dodged a continuous weak layer are some of the low-elevation, sunbaked slopes in the shallow zone (Southeast Mountains).  The southwest quadrant has been particularly productive in the past few days: the combination of a very shallow early-season snowpack now covered by slabs with variable thickness due to wind effects has kept collapses and triggered avalanches going on aspects where we don't commonly see as much activity.  
• Triggered slides will be large to very large right now.  I've looked at the crowns of D3s that ran in West Brush Creek and Mt. Baldy, and in both cases, the snowpack structures look worse than most very large avalanches that I look at.  Those avalanches didn't fail on relatively small-grained, rounding facets that will be an isolated threat in a few days.  They're failing on "pour-out-of-the-pit", large-grained facets that will be very slow to gain strength.    

I have a severe distrust of the current snowpack setup; it has been surprising professionals and recreators around the state all week.  One saving grace for us is the amount of natural activity which has reduced the hazard on slopes that avalanched later in the storm.  Slopes with a consistently deep and uniform snowpack are also less likely to be triggered, provided there are no shallow areas from wind effects, rock bands, etc.