Observation: White Pine Knob

Observation Date

1/3/2025

Observer Name

Pagnucco

Region

Logan » Logan River » White Pine Canyon » White Pine Knob

Location Name or Route

White Pine Knob/Chicken Hill Area

Weather

Sky

Scattered

Wind Direction

South

Wind Speed

Moderate

Weather Comments

Greybird to start the day. Mild temperatures. Saw some blue sky midday with gradually increasing clouds in the mid-afternoon. Moderate winds were only noticeable in exposed terrain and on ridges, Some snow moving but no plumes.

Snow Characteristics

Snow Surface Conditions

Powder

Dense Loose

Wind Crust

Snow Characteristics Comments

Packed powder conditions made for excellent snowmobiling conditions. The solid supportable base is about a 3-4 feet thick dense slab. Ride-anywhere conditions exist, though there are still some just barely buried obstacles out there. Sled track and sled ski penetration is only about 4-6 inches. We found a lot of wind-jacked snow today though the aspects we traveled on (South, East, and North between 8-9,000 ft. had no breakable crusts. Skiing was best in sheltered low angle N-facing terrain on slightly recrystallized snow. We found no damp snow despite the warm temperatures. I think the wind kept heating in check.

Observed settlement and wind scoured areas as well.

Red Flags

Recent Avalanches

Wind Loading

Red Flags Comments

Saw two big slab avalanches from last weekend's cycle that were a bit filled back in. They were each about 4' deep x 300-400" wide. We observed no signs of instability today in our travels but we still stuck to slopes less than 30 degrees. The collapsing and cracking from a week ago have disappeared.

Avalanche Problem #1

Problem

Persistent Weak Layer

Problem #1 Comments

The biggest concern is still the buried PWL - now somewhat deeply buried in the central and north part of the range and less deeply buried in the southern part and possibly the Wellsvilles. There is a deeper snowpack in the central and north, and it's unlikely a skier could trigger something though the weight of a sled might, especially in shallower areas. Near Logan Peak and south, and possibly in the Wellsvilles, there is a shallower snowpack and it's likely a skier or rider could trigger an avalanche failing on the PWL.

Avalanche Problem #2

Problem

Wind Drifted Snow

Problem #2 Comments

There may be areas tomorrow where wind-drifted snow adds enough weight to the snowpack to cause a failure in the PWL or at the old snow/new snow interface. Surface snow today was slightly loose and "faceted."

Comments

Photos:

1. Profile @8900' SSE

2. Profile @9000' E

3. Profile @8600' NNE

4. Still lots of brush poking through in many places.

5. Wind scoured slope.

6. Wind drifted ridge.

7. Wind drifted ridge.

8. Settlement around trees.

9. Settlement and cracking around trees on slope.

10. Supportable snow - only sinking a few inches breaking trail.