Turnagain Pass

No new avalanche activity has been noted since the end of the warm, wet weather on Tuesday Jan 28th – but Kevin did get some great aerial shots of old avalanches from the Jan 17-27 cycle yesterday. There have been only a few folks getting out lately. I’m guessing this is due to the challenging travel conditions, which consist of negotiating a hard surface crust that extends up to 3,000′. Though the sun has been out it has not been able to soften the crust. There may be a few exceptions on steep southerly slopes receiving little wind and direct sun.

Snowpack below 3,000′:
The recent cold temperatures are freezing the snowpack more and more every day. There is still wet snow at the bottom of the pack but this continues to drain. The crust that was over a foot thick is getting thicker.

Snowpack above 3,000′:
This is where the deep slab primary concern comes into play. Though it has been a week since the last known deep slab avalanche (Goat Mtn in Girdwood Valley), it is still on our radar. This is simply because we know faceted snow exists under 3-6+’ of dense slab. A few ways of handling this problem is either to steer clear of steep slopes (35 degrees or steeper) at the upper elevations or hedge your bets by only exposing one person at a time. If the later is chosen, look for the safest ‘relative safe spot’ you can find to watch your buddy. If a deep slab is triggered it could run much further and propagate wider than expected. Lastly, be aware of shallow areas in the slab that can be trigger points – for example, rocks and the tops of rollovers.

Above 3,000′ the surface crust transitions to 4-6″ of soft wind affected snow over a dense base. Many exposed areas have been stripped by the wind and pockets of hard wind slab are scattered in catchment zones and the lee sides of ridges. If you are traveling in these upper elevations harboring dry snow, be on the lookout for older stiff wind slabs as well as any recent wind deposited snow. There is limited loose snow available for transport and I’d expect any fresh slabs to be mostly shallow (in the 6″ range or less). As always, be aware of any cracking in the snow around you.

With many days of unseasonably warm weather during January, some of us are wondering just where did we stack up in the monthly averages. There is more data to crunch so stay tuned – but we do have a few sets of interesting numbers. Below are graphs of precipitation, SWE (Snow Water Equivalent) and Temperature.