UDOT PLANNED AVALANCHE CLOSURES!!

Avalanche: Twin Lakes Pass

Observer Name
Wolfgang Schwurack
Observation Date
Saturday, February 15, 2014
Avalanche Date
Saturday, February 15, 2014
Region
Salt Lake » Big Cottonwood Canyon » Twin Lakes Pass
Location Name or Route
Upper Twin Lake Pass
Elevation
10,000'
Aspect
East
Slope Angle
40°
Trigger
Snowboarder
Trigger: additional info
Cornice Triggered
Avalanche Type
Hard Slab
Avalanche Problem
Persistent Weak Layer
Weak Layer
Depth Hoar
Depth
4'
Width
200'
Vertical
800'
Comments
We kicked out a cornice, east side upper twin lakes pass towards Patsy Marley. One kick broke the cornice. It ran about 200 yards 200 ft wide 4-5’ crown.
Comments

Forecaster comments: Bruce Tremper I heard about the avalanche when I was returning from Cardiff Fork to Alta and went to take a look at it. Brighton noticed the avalanche in the morning and used a helicopter to search the debris with a long range beacon. They noticed a single track coming up from the bottom and the debris covered that track. They could not locate any exit track. But there was no beacon signal in the debris. Although the party reported it to Alta Central, Brighton did not get the word that it was triggered from the top.

In talking with Brighton, we were both concerned that we did not see an exit track. I tried to enter the debris from the north side but it was too sketchy. I pulled back and went in from the top, which was steep and rocky but doable. I searched the debris and found no beacon signal and noticed an exit track in the trees that was not visible to the helicopter. So I declared the debris was cleared.

The avalanche was a deep slab 4-5 feet deep, 200' wide and it was a hard slab that ran on faceted snow just above the rain-rime crust. There was more depth hoar beneath the crust.

Here is an overview of the crown from below. It's much larger than it appears from the ridge. It ran to the faceted snow just above the rain-rime crust.

Looking down the slidepath. The single up track was buried by the debris down in the trees and the track exited to the upper right of this photo in the trees, where it was not as visible to the helicopter.

Here is the single up track I could see from the side of the avalanche, which was buried by debris just above the photo. There was too much dangerous terrain between me and the slide so I backed off and went up to the ridge to get onto the bed surface to search the debris.

Photo of the debris covering the up track I could see from the side.

Coordinates