Southern San Juan
AvalancheMichael Altherr · Jan 10, 2021 · Southern San Juan
Weather
The sky was clear at the beginning of the day. By the end of the day the sky was overcast and it was snowing lightly. Hoar frost (see image) was wide spread on the trees along the ridge line (near TL).
Snowpack
No overt signs of instability. The snowpack seemed relatively solid but recent weather events made it interesting. The area (Cumbres Trestle SnoTel site) had a period of above freezing weather earlier in the past week followed by several days of a hard freeze which left a fairly robust melt freeze layer just below approximately 5" of recent extremely dry snow. The SnoTel site indicated 1.5" of snow in the past 24h. A thin layer of surface hoar and near surface facets was widespread and interspersed with the fresh precipitation particles. Skiing in the open was reminiscent of skiing 'packed powder' at East coast resorts. Dropping into the shadows and the skier dropped into knee deep snow. At the indicated site, I used my avalanche probe to get a sense of layering present in the snowpack. Three hard, presumably melt freeze layers, were found to be separating reasonably firm slabs. No weak layers were detected in this coarse evaluation.
Avalanche
No visible signs of avalanches