Turnagain Pass

Clear skies and good visibility will make it easier to travel into the alpine today.  If you find yourself venturing into steep upper elevation terrain you will need to minimize your exposure and treat all slopes above 35 degrees with suspicion.  A layer of buried surface hoar, which we have been tracking, remains intact on many slopes above 2,500’.  Sitting on top of this layer are 2-3’ dense slabs.  

These stiff slabs have the ability to support a lot of weight, especially where they are thickest.  That all changes when you get onto thinner spots of a slab.  It will be possible for multiple tracks to be put down on a slope without avalanching.  It is important to know that tracks do not equate to stability.

This type of slab/weak layer combo is notorious for catching people off guard days and weeks after a storm.  While we have seen signs of the weak layer gaining strength, we also have no snowpack information from any terrain above 3,500’.

If you decide to get onto bigger and steeper terrain today, it will be crucial to manage yourself and your group appropriately:

Avoid trigger points, such as steep rollovers and areas where the snowpack is thin.
Only expose one person at a time, utilize islands of safety, have an escape route, and communicate plans and decisions effectively.  

Keep in mind that it’s a roll of the dice on all terrain over 35 degrees above 2,500′.  Slabs have the potential to propagate across slopes and carry enough volume and speed to injure and bury a person.

If venturing into steep upper elevation terrain expect to encounter lingering unstable pockets of wind slab, especially on North aspects.  High winds from 2 days ago formed upside down slabs up to 1 foot in depth.  These slabs may be encountered in starting zones and along cross loaded gullies.  Staying off of snow in steep terrain (over 40 degrees) that has a hollow sound or produces shooting cracks will be the best way in managing this concern today.