Avalanche

Cape Horn

Zach PetersonBanner Summit
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Observation photo 1Observation photo 2Observation photo 3

Quick report

Near Cape Horn summit I found a deep, generally stable snowpack, with 4-9' of snow on the ground. January weak layers are buried 3-4+ feet in many areas, and were unreactive in stability tests. The snow surface was slow to warm at middle and upper elevations, becoming moist by mid-afternoon. The lower elevations warmed quicker and several loose wet avalanches were observed along the steep rocky cliffs near the parking lot. 

By 3:30 PM, several small wet loose avalanches (D1-D1.5) were observed in the rocky steep south-facing near the parking lot (see photos).

Weather

Air Temp
30s
Cloud Cover
clear
Wind Loading
none
Recent Snowfall
5-10
Snow Avail For Transport
small smounts

The skies were clear and temperatures were moderate (holding steady in the 30s F in the parking lot). Ridgetop winds were calm to light, from the NW flirting with the W at times.

Snowpack

Surface: 5-10 cms of new snow was observed from yesterday's/ last night's pulse of moisture. Solars were slow to warm today above 8000'—eventually losing the battle to the sun, becoming moist by 2:45 PM. Below 8000', the surface was moist trending to wet by the early afternoon, and several loose wet avalanches were seen in steep craggy terrain near the parking lot. 

Weak Layers: In all areas traveled today, 1/31 weak layers lay below a generally right side up slab, 100-125+ cm thick (F trending to 1F+). Stability tests yielded no results (HS: 275,  ECTX). Weak layers below the slab present as a FC-MFcr combo on SE and portions of E. 

Avalanche

Size
D2 R2
Aspect
W
Trigger
N
Elevation
7600 ft

Photos of a slide that likely happened during the early Feb. storm cycle. The crown was mostly filled in and obscured. The slide crossed the road to the valley bottom below.