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).
Signs of Unstable Snow
Did you see shooting cracks?
Did you experience collapsing or whumpfing?
Avalanche Obs: See above.
-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.
Observed Avalanche Problem #1:
Location: Open areas at TL and ALP; primarily from the NW
Potential Size: Could grow up to D2 in the afternoon on the right terrain feature.
Likelihood of Triggering: Very likely