Avalanche: Turnagain

Location: Pete's North

Date:
Observer:
Route & General Observations

Drove through the Pass down to the Hope Junction to get some road observations. Lots of evidence of snow redistribution from the recent wind events (12/21 & 12/23) and a noted a few avalanches.
Then went up Pete’s North to 2100′.
It is do-able to weave a clean-ish line thru the alders, but you can definitely find yourself trapped in a mess if you take a bad turn!

Avalanche Details
If this is an avalanche observation, click yes below and fill in the form as best as you can. If people were involved, please provide details.
Trigger UnknownRemote Trigger Unknown
Avalanche Type UnknownAspect Unknown
ElevationunknownSlope Angleunknown
Crown DepthunknownWidthunknown
Vertical Rununknown  
Avalanche Details

Saw a few crowns from the road while driving down to the Hope Junction.
A few gullies on the northern half of Seattle ridge had wind slab pockets. The ridge just east of Gulch creek looked to have ran too. Most seemed to have run during the solstice (12/21) wind event, but a fresher looking crowns on Wolverine's Northeast shoulder perhaps ran on 12/23.
See Photos.

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

Lots of evidence of wind loading and recent-ish avalanches.

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

Clear skies.
We only ever felt light winds from the Southwest, but witnessed pluming off the high peaks of Twenty-mile drainage, the Portage area, and south of Turnagain Pass.
Temperatures in the teens.

Snow surface

Wind affected snow surfaces in exposed areas. A fairly soft wind layer capped soft snow in most areas on our tour, but a few pockets of hard wind slab and scoured snow were found.

Snowpack

We dug a pit at 2100' on a WNW aspect. Snow height was 190cm.
70cm slab on top of faceted layers. Slightly shallower here than in other areas around Turnagain. The interface between two faceted layers seems to be most problematic and was the only layer that gave us results in our instability tests. We performed one column test and one extended column test. We got CT 28 that failed with a sudden collapse. Our ECT did not fail until it was overloaded with a couple of boot stomps, which it then propagated a fracture below the stiff slab. The structure for a large destructive avalanche is there!

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.