Observation: Public
Observation Details
Name:
Dallas GlassObservation Date:
February 1, 2021Submitted:
February 1, 2021Zone or Region:
West SouthActivity:
Skiing/SnowboardingLocation:
White Pass BackcountryTriggered Avalanches
Did you trigger any avalanches?
YesWas it intentional?
YesAvalanche Type:
Hard SlabSize:
Size 2: Could bury, injure, or kill a personElevation:
6200Aspect:
NEComments:
I intentionally triggered a small wind slab on a cross-loaded feature. The initial slab ran a few feet then stepped down onto facets below. The propagation of the slide was limited in the feature. The slide was 15" (40cm) deep and 30' (10m) wide, ran about 200 vertical feet. HS-ASc-D1.5-R2-OPhoto:
Observed Avalanches
Did you observe any avalanches?
YesAvalanche Type:
Soft SlabSize:
Size 2: Could bury, injure, or kill a personElevation:
6700Aspect:
NEComments:
I observed a relatively fresh large debris pile in the 2nd Bowl area from the largest of the main chutes. This feature was being actively cross-loaded in the SSE wind pattern. Given the lack of other tracks today I would assume this was a natural. Limited visibility made it impossible to see the crown and determine more information.Signs of Unstable Snow
Observations
Terrain: We took a short tour mainly in the near-treeline band today. From the ski area, we headed to Hogback Mt (2nd peak) before using several lower angled ribs to descend toward Miriam Creek. We also toured above the main Gunsight paths and Gunsight bowl to look at wind loading and avalanche activity.
Snowpack: There was lots of wind loading on some unusual aspect. SSE winds were actively stripping many of the "normal" startzones and loading SE-W-N-NE slopes. Thin reactive cornices were found on these aspects with generally shallow (8" 20cm) slabs. Test slopes produce shooting cracks and small avalanches.
We found the 1/13 crust to be down 15-18" (40-50cm) in nearly all locations with the exception of wind-scoured slopes.
We dug a snow pit at 6050' on a SE aspect in the Miriam drainage looking for the 1/23 FC layer. 1mm facets were seen near a thin melt-freeze crust just a few inches above the 1/13. These gave sudden results in small column test (compression and tilt) but performed irregularly in large (ECT and PST) column tests. These facets show signs of rounding but are still reactive as evidenced by the avalanche above.
Numerous rollerballs at lower (<5500' elevations).
Weather: Overcast with rain and snow showers. Snow level was about 5000-5500'. Moderate to strong SSE ridgetop winds were blowing snow. Temperatures were warm (37-31F).
Media
