Observation: Powder Mountain Backcountry

Observation Date

12/18/2021

Observer Name

Gagne/Duvernay

Region

Ogden » Powder Mountain Backcountry

Location Name or Route

Powder Mountain Backcountry

Weather

Sky

Few

Snow Characteristics

Snow Surface Conditions

Powder

Snow Characteristics Comments

Some surface hoar found in drainage bottoms as well as the near-surface faceting beginning.

HS (height of snow) on northwest through east slopes varies from 50 - 90 cms. Southerly facing slopes 20-40 cms consisting of mostly recent storm snow.

Red Flags

Cracking

Collapsing

Poor Snowpack Structure

Red Flags Comments

Numerous loud collapses and cracking. Comments on poor snowpack structure follow.

Avalanche Problem #1

Problem

Persistent Weak Layer

Trend

Same

Problem #1 Comments

Found 10-30 cm layer of faceted snow on northwest - north - east aspects above 8000'. The weakest snow was 2 mm grains of well-developed facets just underneath the recent storm snow.

Full propagation with extended column tests ranging from ECTP3 - ECTP18. All were failing on faceted layer just underneath recent storm snow.

Snow Profile

Aspect

North

Elevation

9,200'

Comments

Widespread collapsing and cracking kept us to slopes less steep than 30 degrees on aspects facing northwest through east. Recent storm snow slab is F-hard near the surface and increases to 1F right at the interface with old, faceted snow surface prior to storms beginning on 12/9.

Southerly-facing slopes had at best patchy snow prior to recent storms so this will be go-to terrain for the time being as there is no weak snow on these aspects.

Some minor cornice development noted along ridges.

With the exception of upper elevation aspects facing northwest through east where there is a Considerable avalanche danger due to a stronger slab on top of the persistent weak layer of facets, most of the terrain in the area we explored has a Low or Moderate danger where the primary concern is a shallow wind drift and loose sluffing on steep aspects.

Thanks to snow safety team at Powder Mountain for assisting us getting into their backcountry terrain. The UAC values the relationships we have with Utah resorts. Thanks!

Video with discussion of snowpack.

Video