Observation: Public
Observation Details
Name:
Josh HirshbergObservation Date:
April 9, 2021Submitted:
April 10, 2021Zone or Region:
Stevens PassActivity:
Skiing/SnowboardingLocation:
3 mile SSW of Stevens PassObserved Avalanches
Did you observe any avalanches?
YesAvalanche Type:
Wet LooseSize:
Size 1: Relatively harmless to peopleElevation:
near and below treelineAspect:
SWComments:
2 natural avalanches in Tunnel creek, Glory Bowl, 5,200ft. Size D1.5. Occured around noon.Many roller balls bordering on wet loose on SW-SE in Trapper creek. Avalanche activity was more limited by cloud cover west of the pass compared to just east of the pass. Significant avalanches easilt to size D2 on S-SE of Lictenberg and Rock mtn
Photo:
Signs of Unstable Snow
Observations
Besides avalanche activity, the most notable observation was greater storm totals and a potential poor bond (though isolated) in the recent snow just above the 4/7 interface:
38000ft in a meadow:
height of new snow was 38cm
↓30cm- 1F hard, moist, new snow.
↓38cm 1F hard, melt form, semi-frozen
4500ft, NNW, 36deg slope:
height of new snow was 48cm
↓46cm- easy, clean hand shears where 1F moist storm snow sat on softer dry storm snow just above the 4/7 crust. We also noted that the lower storm snow had a punchy feel underfoot from 4,000-4,500ft. This seemed to coincide w strong-over-week layering that produced easy hand shears.
4900ft, NW 35deg slope
height of new snow was 59cm
hand shears on the 4/7 crust were moderate, planar, but rough. 4/7 crust was still only 10cm thick, more frozen than at 3800ft, but still had underlying weaker melt-forms.