Observation: Turnagain

Location: Eddies

Route & General Observations

Eddies to 2600′

Red Flags
Red flags are simple visual clues that are a sign of potential avalanche danger. Please record any sign of red flags below.
Obvious signs of instability
Recent Avalanches?Yes
Collapsing (Whumphing)?No
Cracking (Shooting cracks)?No
Observer Comments

No new slides today that we observed, but recent avalanche activity on Eddies and Sunnyside - as others have reported - is quite impressive!

Additionally, a small loose snow avalanche from Sharks Fin ridgeline released mid-storm on a steep SW aspect, and as it slid down the slope it triggered a small slab that looks to be similar to the other recent slides (~2' deep) in depth was triggered. This looked to be a D1.

Across Turnagain arm, a mid-elevation slab occurred in day(s) prior running into Peterson Creek (see photo below)

And finally, a dark glide crack was also seen on a steep face behind Penguin Ridge, that looks to be rather fresh given two weeks of snow... (see photo below)

Weather & Snow Characteristics
Please provide details to help us determine the weather and snowpack during the time this observation took place.

The trend of BRRR at the car continued, with temps just below zero at the start and finish of the day. Few clouds, and felt above zero on the ridgeline with occasional NE light winds up high.

Snow surface

Surface hoar has formed on any non-treed areas of the route, from the trailhead to ridgeline, ranging in size from 3-6mm. It sat on soft snow along the entire route, with ski penetration 6-10" except a few spots above 2500' where there was just 2-3" of soft snow from the past week.


Dug several times along the route to see how surface hoar/facet layer cake is baking...

Pit #1: 2600', West aspect, 25 degree slope, Height of Snow (HS)=310cm. This pit was dug ~100 yards downhill of the upper debris pile from Thursday's slide, and ~50 yards from the edge of where runout continued down to the valley floor. Test results are below.

Pit #2: 2100', N aspect, 20 degree slope, HS = 195. This pit was 20' from the pit submitted on 11/27. Results are below, and while the tests failed with more taps at the 11/22 buried surface hoar interface today versus last week, they had more 'pop' this week.

Pit #3: Quick pit just deep enough to reach the 11/22 buried surface hoar at 1100' on a NW aspect. CT 17, 19 RP and ECTP 17 down 50cm from the surface. The snow above the 11/22 layer was fist -> 4 finger hard - softer than the other two locations - and the shovel had compressed more than half the block when failure occurred.

Photos & Video
Please upload photos below. Maximum of 5 megabytes per image. Click here for help on resizing images. If you are having trouble uploading please email images separately to staff.