Avalanche: Rock Canyon

Observer Name
Dave Jarvis
Observation Date
Friday, April 14, 2023
Avalanche Date
Wednesday, April 12, 2023
Region
Provo » Rock Canyon
Location Name or Route
Crows Foot Couloir & Grrr Couloir (ect.)
Elevation
9,900'
Aspect
Southwest
Trigger
Natural
Depth
6'
Width
300'
Comments
When I scanned the area of Cascade Face North and East of Rock Canyon Campground, I counted
nine avalanches that had come down earlier this week. Clearly a natural cycle triggered by multiple
days of increased heat and solar heating.
From the West:
A smaller avalanche West of the Grr Couloir. Not too big. South aspect. Fanned out, left a dirty
debris pile about 75' x 150'.
The Grr Couloir ran fully from the top at 10,000'. South aspect. Scoured deeply. Left a rock
ledge about mid-way. (bummer for the skiers) Left debris in the lower section. Blasted across
the road leaving debris about 15' to 18'deep. Fairly clean snow, smaller lumps.
Another smaller one above & to the West of the Foot. Dropped out of some cliffs.
Crows Foot Couloir. This thing went totally psycho this time... I could see two
sections of 5'-6' Crown Fracture about 150' below the ridge. One facing South,
the other due West. The debris shot out of the defile at the base of the Crows Foot
with very large chunks of muddy, damp, and hard snow. It blasted through more
of the previous debris over the road. It must have run quite a while. I counted at
least 8 separate tracks. Multiple tall vertical sided walls. More broken trees from
above. The longest run went a full hundred yards further than the second
avalanche's. Leaving a 30' wall stacked on the Second Left Hand trail. The Toe is
almost to the base of the hill on the West side of the valley. (marker pin on map)
Brutal, violent,and probably unnervingly loud for the duration. Did I mention
really dirty? There used to be a forest of Maple, Box Elder, Aspen, and a few
pine. Flattened better than a couple of Dozers with an anchor chain.
Snowmobiles, Snow Bikes etc. won't be getting across or around for a while.
Next the four open spaces East of the campground, West aspect. The three larger ones
ran fairly big. With a plenty somewhat dirty debris. None reached the road. #4 was about
a third the size. All started high up near the top of the ridge.
On the south end of the face is a smaller, shallow damp run that ends above the
mouth of Dry Fork.
Crossing the dugways either side of Second Right Hand overlook, there was a legit
concern of stepping off the pack and having to deal with steep hard slab. The West
one had a couple of places that had pulled out as if there was a glide going on. Like
a little Bergschrund. Sweet.
Coordinates