Observation: NWAC Forecaster

All Observations

Basic Information

Observation Details

Observation Date:
February 14, 2023
Submitted:
February 14, 2023
Observer:
NWAC Forecaster - Andy Harrington
Zone or Region:
Snoqualmie Pass
Location:
Draft Dodger Ridge

Signs of Unstable Snow

Recent Avalanches? 
Yes
Cracking? 
None Experienced
Collapsing? 
None Experienced

Media/Attachments

A very small pocket of wind-drifted snow failed during a ski cut on a test slope.
The new storm snow was generally rightside up and had a favorable bond. There were some storm instabilities that showed up during small column tests. Primarily one about a foot below the surface.
Wet Loose avalanches initiating out of steep rocky terrain.
Loose avalanches were triggered by snow shedding from trees and rocks. Although triggered by sunshine, most of them involved dry snow.
A large debris pile was found below Bryant Peak and it's popular couloir. The debris almost ran into Source Lake and had a few inches of snow on it. The slide likely occurred overnight on 2/13.

Advanced Information

Weather Summary

New/Recent Snowfall:
~2 feet at upper elevations. Closer to 1 foot lower down.

Blue skies and sunshine. It was a gorgeous day.

Avalanche Observations

 #  Date Location Size Type Bed Sfc Depth Trigger Photos Details
1 Feb 13, 2023
() 		Bryant Peak
N 5500ft 		D2.5
R2 		HS-Hard Slab 3ft NC-Cornice Fall
Photo of crown from the NE of slide path
Debris field looking down Bryant Couloir
Photo of crown directly below slide path
Slabs in higher elevation terrain that likely failed during the 2/13 avalanche cycle. Some of these may have filtered into a popular skiing couloir that had a large debris pile below it.
A large debris pile was found below Bryant Peak and it's popular couloir. The debris almost ran into Source Lake and had a few inches of snow on it. The slide likely occurred overnight on 2/13.
Public Field Report: Top of Bryant Couloir/wonder gully
Public Field Report: Top of Bryant Couloir/wonder gully
Public Field Report: Top of Bryant Couloir/wonder gully
Public Field Report: Bryant
Public Field Report: Bryant
Report
Bryant Peak

Widespread loose cycle - including both dry and wet from what I could tell. Most of these were small, but a few may have approached D1.5. There was a very large debris pile below the Bryant Peak Couloir that almost made it into Source Lake. Probably a D2.5, but I could not see the start zone/where it actually initiated. Will be interested to find out later.

Snowpack Observations

I traveled up the Alpental Valley to Source Lake then up to Draft Dodger Ridge. Dug a pit at 4600' on a N-facing rollover. Then made two laps down to Source Lake before I had to head back to the car and navigate the parking lot nightmare.

There was plenty of soft and fluffy snow right from the truck with snow increasing significantly as you ascend in elevation. Hand pits were a bit uninspiring but would fail with enough of a tug on the moist snow at the base of the HST. Where I dug it may have been a little wind-loaded, but I measured 58cm over the 2/13 interface. Alp Pro Patrol later reported a similar depth on their manual stake on Disposal Ridge. The snow was generally right-side up, but a midstorm layer continually showed up during small column tests down 31cm. I was able to find some graupel/rimed PP mixed into the snow a few cms above the 2/13 interface, but it was unreactive in this location. Classic graupel. The 2/13 interface was 5cm thick and freezing but not yet fully frozen solid. It was ski but not boot supportable.

I kicked off the smallest wind-loaded pocket on a steep convexity with a ski cut. Hard to even call it a pocket, more like some blocks of snow. Uptrack tests had a few soft blocks failing, but not consistently. The snow seemed to lack a lot of slab characteristics during my time out. Loose avalanches and falling in a tree well were more of a concern.

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