Turnagain Pass

Skies cleared on Sunday allowing for many people to venture into the higher terrain at Turnagain Pass. This was the first test of the snowpack since 16-24″ of snow fell on Friday night through Saturday. It didn’t take long for several large avalanches to be triggered by people. All but one was remotely triggered from either the side or top. Here is a rundown:

• Tincan, Hippy Bowl:  Remotely triggered, no one caught. Broke in faceted snow near the ground (basal facets). Several hundred feet wide and running 2,500′ to the creek below.
• Sunburst, SW face:  Skier triggered while skier was on slope. Skier was very lucky to have been able to ski off the slab to safety as avalanche broke above skier. Released in basal facets taking entire snowpack. Several hundred feet wide and running to valley bottom.
• Eddies, mid elevation rollovers:  Remotely trigged, no one caught. Broke at the new/old interface in buried surface hoar, stepped down to basal facets in spots. Up to 1,000′ wide.

A big THANK YOU to the 10 people who passed along their information from these events. See all those reports HERE.

Tincan’s Hippy Bowl. Avalanche was triggered remotely by a skier on the low angle terrain on the looker’s left side. Skier was well out of the way and no one was caught. 11.22.20. Photo: Henry Munter

Close up of the crown, note how the weak layer failed across the entire slope taking multiple sections just below the ridge. 11.22.20

Close up of the sympathetically triggered pocket below Hippy Bowl, also released in the facets near the ground. 11.22.20

Sunburst, SW face, large avalanche that was triggered by skier on the slope. This avalanche also broke near the ground in facets. 11.22.20

Eddies avalanche in mid elevation rolling terrain, up to 1,000′ wide. This was remotely triggered from the side/top and no one was caught. Avalanche broke in buried surface hoar at the new/old snow interface and stepped down to the basal facets in places. 11.22.20. Photo: Andy Moderow

The proof is undeniable – we have a bad setup for human triggered large avalanches. Add to that, a lot of people, including myself, are stoked to start the winter and get into the backcountry. Several bullets were dodged on Sunday and the same conditions will persist through the Thanksgiving holiday.

It’s a HEADS UP situation. Several feet of recent storm snow sits on a very weak base of sugary faceted snow. This is keeping all the new snow from sticking well to the slopes and why people are able to trigger these large avalanches. Furthermore, a layer of buried surface hoar sits under last weekend’s storm snow and is likely to still be reactive. Hence slabs releasing around 2 feet deep are likely along with a slab that releases 3-4′ deep and near the ground.

Not only is watching out for RED FLAGS a wise decision, but simply letting the mountains do their thing and adjust to these new loads of snow. We all want to return back to the parking lots with high fives. Sticking to low angle slopes, and out from under larger slopes, is a great way to enjoy the new snow.

As a reminder, here are the Red Flags to look for:
– Recent avalanches
– Whumpfing (collapsing) of the snowpack
– Shooting cracks

Below is a look at the snowpack from Tincan on Sunday. Note the few inches of weak snow at the bottom of the snowpack.

Roughly a foot of new snow fell yesterday, Monday, and another 6-10″ of snow is expected tomorrow, Wednesday. This has been, and will be, accompanied by strong easterly winds. That said, storm snow avalanches will be likely, especially tomorrow.

With temperatures rising during tomorrow’s snowfall, making for an ‘upside down’ storm, expect shallow storm slabs to form. This is due to denser snow falling onto lighter snow. Additionally, wind slabs will be forming tomorrow as well. If they begin to release naturally, could step down and trigger a much larger natural avalanche. More reason to avoid avalanche terrain for the time being.