Turnagain Pass

Cloudy skies, cool temperatures and light winds will not impact avalanche conditions today and a Normal Caution (LOW danger) regime remains in place. The one exception is the glide avalanche. We have seen several small glide cracks release into avalanches in the Girdwood Valley and Turnagain Pass during the past two days. Although many of these slides are on the smaller side and in areas not commonly traveled, there are some current issues on Seattle Ridge. Several cracks have opened up along the ridge and one of these released Friday, Mar 1st. As far as the older glide cracks we’ve been monitoring in popular areas such as Magnum, Lipps, Cornbiscuit, these do not appear to be moving as quick. PSA: Help us keep track of these cracks and send us a photo! 

Things to keep in mind if you are headed into the backcountry:

• Glide avalanches – These types of avalanches are highly unpredictable and not associated with human triggers. It’s always best to watch for and limit exposure under glide cracks.
• Dry-loose sluffs – Watch your sluff on steep shaded slopes.
• Cornice falls – As always, give cornices a wide berth. 
• An outlier slab avalanche – Although it is unlikely a person could trigger a slab avalanche, the mountains can harbor surprises, especially in thin snowpack areas. Considering the consequences before entering into high consequence terrain and maintaining good travel protocol are good habits to keep on LOW danger days.

Surface conditions? In general, a stout sun crust has been found on southerly facing slopes. Otherwise, 4-8″ or so of soft re-crystalized (near surface faceted snow) sits over a firmer base on shaded aspects. In anticipation of the next storm, we are closely mapping the surface conditions as well as watching for new surface hoar growth. 

The ‘State of the Glide Cracks’ along the front side of Seattle Ridge seen from the motorized parking lot.

South of Turnagain – Summit Lake and Silvertip zones:  For anyone traveling in this area note that a shallow snowpack with a generally poor structure exists. A variety of old weak layers (facets and buried surface hoar) sit in the mid and base of the snowpack. It is uncertain as to how reactive these layers are at this point and if they could produce a slab avalanche. We do know whumpfing has been observed in the Summit area and last Thursday’s (2/21) wind event triggered many large slab avalanches breaking in deeper weak layers. Assessing the slab as well as the weak layer will be important. Old wind slabs in steep terrain sitting on weak snow are the most suspect places to trigger an avalanche.