Avalanche: Rock Canyon

Observer Name
Dave Jarvis
Observation Date
Thursday, March 16, 2023
Avalanche Date
Wednesday, March 15, 2023
Region
Provo » Rock Canyon
Location Name or Route
Rock Canyon Crows Foot Couloir
Elevation
10,400'
Aspect
South
Trigger
Natural
Depth
4'
Width
500'
Comments
When I approached Second Right Hand Overlook on Thursday 3-16-23 I noticed that the Crows Foot Couloir had
run again,, big time. I could see that it had come out of the Crows Foot proper. There was lots of debris down
slope for several hundred yards. I could see a crown fracture running close to 200 yards long near the top of the face
above the West finger of the Crows Foot. Just below the 3-way junction on the ridge. (3' to 5' height) There was enough debris that I wouldn't be surprised if more of the high faces ran.
I headed up the campground entry road and north up Squaw Peak Road. A couple of hundred yards before the older
avalanche I noticed the snow had a dusting of fine dirt. Then small pieces of green and dead pine were everywhere.
Fallout from an air-blast.
I walked up the older ramp of snow and stopped next to a 7' vertical drop cut into the older debris. Beyond, a maze of repeated runs carved out like toboggan runs. Steep walls built up and carved out with the next surge. And, enough piles of mashed potatoes to feed most of Utah for a week... The debris ran 4 to 5 hundred yards down slope before it turned out of sight.. I placed the map pointer about where I could still see debris. The multiple runouts also fanned out as they blasted down slope.
The estimated 70' of debris piled on the road from the 1-4-23 avalanche was carved 15' to 20' lower. There is an area of cliff and slope to the west and above the upper runout that looked like it was hit by the air-blast. The lower
200 yards of the Grr couloir had run. I'm going to call that a sympathetic even though it's a few hundred yards to the
West.
I could count 6 different routes cut out by different runs. There could be more. Just bench-racing... I think this might have started between 11 am and Noon, then run repeatedly through the day, as different areas of the upper
slopes heated and failed. A single run is, well, "inconceivable".
This avalanche is going to be impassable by Snowmobile or snow-bike for several weeks at a minimum. Too many
vertical faces that will harden up. It would be a long ride from Hobble Creek to find that out.
Boy,, the dynamics and energy involved in an avalanche of this scale is mind blowing. I said mashed potatoes, but
much it was more like endless rounded hard balls of very firm snow. Many very large. I doubt that it came out of the defile at the base of the couloir like that.
When I got back down to Second Right Hand Overlook, I watched the west fork of the Crows Foot run for about a
minute.
Coordinates