Observation: Garden City Bowls

Observation Date
12/31/2017
Observer Name
Brett Verhoef

Region:

Location Name or Route
Bear River Range, Garden City Bowls
Weather
Sky
Clear
Weather Comments
Clear and cold after a clear cold night.
Snow Characteristics
Snow Surface Conditions
Powder
Wind Crust
Snow Characteristics Comments
1/2" to 3/4" thick collapsible, hollow wind crust on the ridge between Swan Flat road and Garden City Bowls. Similar wind crust on the northeastern slopes of Garden City Bowls. Powder in the central Garden City Bowls.
Red Flags
Red Flags
Wind Loading
Collapsing
Red Flags Comments
Collapsing observed on the ridge of Garden City Bowls but none observed on eastern slopes, even the 30° wind blown slopes at the northeastern end of the ridge.
Avalanche Problem #1
Type
Wind Slab
Problem #1 Comments
On top of the ridge there was clearly snow transport from the previous few days.
Avalanche Problem #2
Type
Persistent Slab
Problem #2 Comments
A snow pit on the northeastern slopes of the Garden City Bowls area showed the presence of the persistent weak layer (4 to 6" thick faceted sugar) below the Christmas storm snow (10 to 12" of dense powder).
Snow Profile
Aspect
East
Elevation
8200
Slope Angle
30
Comments
Despite the snowpack observations of a persistent weak layer below the Christmas snow slab, no collapsing or cracking was observed on the 30° slopes in the northern end of the Garden City Bowls area. This was contradicted by an ECTN test that collapsed at 16 strikes. It appears the storm slab is strong enough to support a skier, which may not be the case everywhere, especially in areas around trees and rocks where the slab may be thinner. These slopes had been skied at least a half dozen times in the last two days.
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable
Snow Profile Coordinates