Turnagain Pass

Finally, the winds look to let up… After 11 days of sustained moderate to strong easterly ridgetop winds across our region, weather models show a slow decline beginning today. As we might expect, the snow cover has been significantly reshaped in the Alpine where it has been snowing for the past 11 days as well. Windward areas are scoured to the tundra and catchment zones have drifts over 10 feet deep. The good news is, much of the terrain we like to play on seems to still have a decent degree of snow cover.

Wind slab avalanches are the main concern today. Fresh slabs could be found from the overnight winds or in areas still seeing some wind loading today. On top on that, older wind slabs from yesterday or prior could still pose an issue in steep wind loaded terrain. What to watch for:

• Wind loading patters- where has the snow been depositing and scouring.
• Be extra wary of wind loaded steep slopes at the high elevations. This is the most likely place to trigger a wind slab.
• Stiffer snow over softer snow- does the snow feel hollow under you?
• Is the snow cracking around you? Do you hear/feel any whumpfing?

These are all signs a slab has been found and if the snow cracks and buckles with our weight, we’ll know it’s telling us it’s unstable. As always, before jumping onto a slope, it’s good to consider the consequences if an avalanche is triggered.

Active wind loading along Sunburst Ridge yesterday. Winds were blowing northeasterly and loading the SW side of the ridge.

Cornices:  If traveling along ridgelines, give cornices a wide berth, they have grown and could be teetering on the balance. Limit exposure under them as well, especially if there is a group of people above you along the ridge.

Small natural cornice fall yesterday, also along the SW face of Sunburst. Note the larger cornices further down ridge.  

The glide avalanche cycle from last week has slowed down dramatically. There are a few cracks in the Turnagain area we know of. These are good to avoid being under, two in the Tincan Trees and one just above alder line under Common Bowl on the SW face of the ridge, pictured below. You never know when cracks appear – always keep a lookout for them as they can release into an avalanche at anytime.

As we head into a clear sky period and travel further off the road into the Alpine becomes possible, keep in mind there could be some lingering funny business deeper in the snowpack in shallow snow cover areas such as Summit Lake. Various layers of facets and crusts could still remain intact at the high elevations. If this is the case, the potential exists for a larger avalanche to be triggered that breaks deeper in the snowpack.

Also of note, in a pit dug at 3,500′ on Sunburst yesterday, we found the old Nov Veteran’s Day facets over the hard basal melt-freeze crust at Turnagain. The layer didn’t show signs of reactivity here, which is good news (yet still something we are tracking). We dug in a shallow zone to find it as the layer is now buried between 3-6′ deep and even more in places.