Observation: Public
Observation Details
Name:
Zack WentzObservation Date:
February 11, 2021Submitted:
February 11, 2021Zone or Region:
Snoqualmie PassActivity:
Skiing/SnowboardingLocation:
Roaring Ridge - Christmas Tree BowlTriggered Avalanches
Did you trigger any avalanches?
YesWas it intentional?
YesAvalanche Type:
Soft SlabSize:
Size 1: Relatively harmless to peopleElevation:
3700'Aspect:
NComments:
Location: Immediately below ridge crest in an opening below an old logging road at treeline in Christmas Tree Bowl. Avalanche Depth: 15cms -Small sz 1 Sc on a 35 degree convex roll immediately below ridge crest. Slab was 1F- in hardness and sitting atop F hardness faceted new snow. Slab was very touchy, and resulted in propagation to the extent of the start zone (small test slope).Photo:
Signs of Unstable Snow
Did you see shooting cracks?
Yes, IsolatedDid you experience collapsing or whumpfing?
NoObservations
Avalanche Obs: See above.
Snowpack Obs:
-Numerous hand shears were conducted on various aspects ranging from NW-NE in open areas at BTL and TL. We got numerous resistant planar results down 31cms on a storm interface. 10-15cms of F hardness snow sits atop gradually denser snow below.
-On N aspects at TL and ALP, there is significant new wind effect and touchy wind slabs. 15cms of 1F hardness wind slabs sit atop 10cms of F hardness new faceted snow.
-Before dropping into our line at 3700' on a N aspect at TL, we checked out the snow and checked for presence of the 2/1 & 1/13 FC/MFcrs. The 2/1 interface was found down 140cms and the 1/13 interface down 165cms through probing. The reactivity of these layers was not tested for during collecting these field obs.
Weather Obs: Overcast & cold. Pass temps averaged 20 degrees F. S-1. M-S winds from the SE, with moderate blowing snow in open areas exposed to the wind.
Media
Advanced Observations
Observed Avalanche Problem #1:
Wind SlabComments:
Location: Open areas at TL and ALP; primarily from the NWPotential Size: Could grow up to D2 in the afternoon on the right terrain feature.
Likelihood of Triggering: Very likely