Avalanche: Turnagain

Location: Tincan Library

Date:
Observer:
Route & General Observations

Toured from the Tincan parking lot to the Library. Skinned and skied one of the first lines in the Library. Continued down the valley towards Kickstep, noting two other groups on different lines in the Library. We were in communication via radio with one party the whole day, coordinating our movements.

We decided to avoid the two other parties and push further down the valley when the dense fog layer that had consumed the lower areas started moving in. We lost visibility of the ridge above so we decided to skin and ski a shorter line with a rocky face above it so we could see everything above us. As we were approaching the gut we started seeing roller balls come down from above. We noted that the snow was rapidly warming. A few moments later we saw a natural loose snow avalanche in a nearby gully that started from a rocky area of the ridge and moved a significant amount of new snow down the gut, presumably from the rapid warming. We decided to heed this red flag and retreat to a safer area and ski the Tincan trees. We announced the avalanche on the radio with one of the other parties in the valley and exited.

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 NaturalRemote Trigger No
Avalanche Type Dry Loose SnowAspect South
Elevation 3400ftSlope Angle 50deg
Crown DepthunknownWidthunknown
Vertical Run 1000ft  
Avalanche Details

We observed a natural loose snow avalanche that occurred during the rapid warming around 1-2pm. It started at the top of the ridge and ran down to the apron, filling the gully we were considering climbing so we retreated and skied Tincan Trees.

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

The cloud coverage near the road had not made it into the Tincan Creek valley so the South face of Library was baking in the sun from around noon until 2pm when the fog started rolling in. During this time roller balls started coming down and the snow/conditions were rapidly warming.

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

Clear, calm wind, 25ish degrees. Clear and sunny until around 2pm when a dense fog started moving into the Tincan Creek valley.

Snow surface

We did not find any sun or wind effected snow until the rapid warming. The sun started heating up the snow so much that we experienced glop/sticking to our ski bases (no skins) on the exit of the Library. Our one run on the Library and second run in Tincan Trees consisted of all new soft settled powder.

Snowpack

No stability tests were performed.