Northern San Juan
AvalancheBill Nalli · Mar 9, 2020 · Northern San Juan
Snowpack
Went to investigate how the below treeline zone is handling the warm temperatures and to see if the slight cooling has helped sintering of the older weak faceted snow. At 11,400' the shadier, northeast aspect was strong and did not show much effect from the warming. Not all northeast slopes are similar and many areas exist with a shallow weak structure. Quickly noticed that the sunnier southeast was very different. Localized collapsing around my skis highlighted a saturated weak, shallow snowpack on southeast. As I descended it only got worse and I was sinking to the ground. A snowprofile showed the surface melt-freeze crust to be wet with liquid water visible between crystals. This plus low stability test scores plus warmer steep terrain below caused me to retreat and exit back out to the ski area. Liquid water holds heat longer than you expect and poor structure prior to the warming has caused low elevations to remain unstable.
Avalanche
Small loose-wet slides were seen in very steep west-facing terrain.