Northern San Juan
AvalancheAmy Pertuz · Dec 15, 2019 · Northern San Juan
Weather
Today’s vertical snowfall and soft surface conditions betray the rude, gusty, flip-flop winds of yesterday, which created wide-scale rearrangement of alpine and near tree line snow, creating wind slabs and bare slopes up high and thickening the snow below treeline in spots. Temps cooled during the day, steady snowfall, typically S3. Some NW winds in the afternoon moving some alpine snow, but no significant blowing snow.
Snowpack
Storm total 20”. NE slopes received a lot of drifting yesterday and have more storm snow overall than Westerly aspects (including NW and SW), many of which are stripped or variable underneath today’s fluff. Storm snow fell right side up, but it may now be hard to recognize yesterday’s wind-slabs. Deceiving. HS 152cm, NE aspect, Upper limit of BTL. Depth hoar here is 20cm deep, but strengthening slightly, and less reactive than some places. No propagation in large column tests. No signs of surface hoar or other significant weak layers in upper snowpack here.
Avalanche
None observed. Alpine start zones not visible. No cracking, collapsing, avalanches. Good skiing!