Gunnison

The lingering potential to trigger a large and dangerous avalanche on colder, shadier aspects should dictate your travel habits.  A large remotely triggered avalanche near Irwin on Friday and numerous shooting cracks in Cement Creek yesterday highlight that our buried weak layers remain a threat.  You can reliably avoid the problem by riding on southerly aspects or on lower angle terrain.  Otherwise, careful snowpack assessments and terrain selection are essential if you plan to ride on steep northerly or east aspects.  

Patterns.  Patterns. Patterns.  Although persistent slabs are notorious for providing erratic feedback underfoot, paying attention to their patterns, both at a local and statewide scale can help us make informed decisions. 

The first striking pattern is that we've had 3 fatal accidents around Colorado, at least 5 other significant accidents that involved burials or injuries, and dozens of close calls since our problematic weak layer was buried in mid-February.  I think people continue to get surprised because we had a December-esque weak layer buried and activated during a time of the season when we are used to seeing a stronger and more trustworthy snowpack in March.  

Another important pattern, both locally and statewide, is that since our warmup in early March, slab avalanches breaking on old layers have been almost exclusively on Northwest to East aspects, with only a few on West and on high elevation Southeast aspects.  That's because the warmup in early March, along with more recent spring-like weather, has transformed the sunnier, warmer aspects to a spring-like snowpack characterized by strong and thick crusts that thwart deeper instabilities.  So if you want to reliably avoid surprises, choose objectives on more southerly aspects.  The snowpack has stayed dry and winterlike on the colder, more northerly aspects.  

And finally, the Crested Butte forecast area saw extensive persistent slab activity in late February which has tapered significantly in the last week or so, whereas other parts of the state have been more active in the past week. (Here are a few examples of large avalanches from neighboring zones over the past few days: A, B, C, D.) This pattern seems to be rooted in the storm track over the past month.  We were in the bullseye for heavy snowfall in late February, and had a "crush and flush" storm and avalanche cycle.  We've since been in the CB "donut hole", meaning that storms have favored other parts of the state.  Today's storm looks to follow the same trend. The early and heavy loading on the weak layer followed by subsequent quieter weather in the past week has played favorably for our persistent slab concerns, allowing many slopes to adjust.  The odds of triggering an avalanche continue to decrease. Identifying those lingering troublemaker slopes can be challenging and involves some uncertainty.  Thus, it's important to circle back to the first two points: there is potential for surprises, and they will almost certainly happen on the colder, shadier aspects.  Keep that in mind when choosing your routes and making snowpack assessments.