Avalanche: Rock Canyon

Observer Name
Dave Jarvis
Observation Date
Sunday, February 16, 2014
Occurrence Date
Thursday, February 13, 2014
Occurence Time
Unknown

Region:

Location Name or Route
Provo Rock Canyon, Crowsfoot Coulour Cascade Peak. SW
Elevation
10500
Aspect
Southwest
Slope Angle
Unknown
Trigger
Natural
Avalanche Type
Soft Slab
Avalanche Problem
Storm Slab
Weak Layer
Density Change
Depth
unknown
Width
250
Vertical
3500
Comments
On 1-26-14, the area this avalanche started was mostly clear to the ground. So, it was a combination of snow from the storm prior to 2-2-14 and the rain-snow event of 2-9-14. It could have been triggered by wet snow during the 2-9 storm or warming later in the week. It ran down the Crowsfoot Coulour and buried the road at the corner north of Rock Canyon Campground, and ran down slope of the road. The light was a bit flat and I didn't spot a crown fracture. The Coulour just to the west also ran to a lesser degree.
Comments
Coming up Rock Canyon, the "terrain Trap" runouts below the first bridge, hadn't run during the 2-9-14 event due to lower altitude rain. The rocky draw on the north side of Y Mountain had 3 avalanches. The debris pile on the east was fairly large and about 150 yards up-slope of the trail. The middle and west ones were much smaller and stopped at higher altitudes.
Comments
I did a quick pole-pit at 6500'. The pack was uniformly damp for about 2' with 6" of coarse wet facets near the ground. The storm front wind had started up around 11am. By the time I got to Second Right Hand Overlook, a bit of a Freight Train was blowing from the West Southwest. The North-West ridges of Provo Peak from 8800' to the summit had long columns of leeward spindrift. There was an area about 500' down the west ridge of Freedom Peak with a trail of blowing snow. I've seen wind-drifts in this area the last couple of months, leeward of rocks and trees. Two locations a bit lower had peeled off wind-slabs a couple of weeks ago.
Coordinates