Northern San Juan
AvalancheMatt Steen · Jan 11, 2018 · Northern San Juan
Weather
Partly cloudy mid morning. Cloud cover had a hard time clearing out after Wednesday night, Thursday mornings storm. Some light snow showers associated with some enhanced orographic locations around peaks and ridges.
Snowpack
90 to 120 cm of freshly deposited snow from this past week sits on top of 10 to 20 cm of large grained faceted snow. Widespread collapsing and cracking observed on above and near treeline northerly aspects. CT 1 and 5 resistant planer 10 and 50ish cm down from the surface. CT 9 sudden planer at the facet interface.The snowpack now rests delicately on old snow. It is very weak and needs respect. It will only get worse as the slab settles. It will gain strength, and put us classically into the lowering of probability, with the consequences high. Yuck. We all want to get the fresh snow. Please ease into terrain that you are familiar with THIS SEASON. Every years snowpack is different. This ones is an outlier. Please respect and be safe out there.
Avalanche
Numerous natural avalanches released either Wednesday night or from our previous loading events from earlier in the week. Mostly covered debris with noticeable crowns below steep slopes and rock faces. Some crowns hundreds+ feet wide. During our low-angle decent we managed to collapse slopes 3 times. One collapse triggered 4 remote avalanches all at a 'safe distance' to our party. If the slab had been more cohesive, 'safe distance' wouldn't be in this post. One slide released about 1/4 mile away. All of these crowns were at the interface 2 to 3 feet deep. Most were R1 D2's with a couple smaller slides.