Northern San Juan
AvalancheColin Mitchell · Feb 23, 2024 · Northern San Juan
Weather
Clear skies with a few high, thin clouds. Brisk in the morning, but warmed up nicely by midday. Northwest winds were light and gusty.
Snowpack
I traveled on north-east-southeast slopes up to about 11,500' in elevation. North-facing aspects had about 20 cm of loose, faceting grains above a stout mid-pack slab. As I moved onto east aspects, I began to encounter some intermittent melt-freeze crusts on the surface. Some areas were unaffected, but micro aspects with more sun exposure and steeper slopes had a thin, breakable crust. Southeast-facing slopes were my observation target. These aspects had a continuous crust that became noticeably stronger as I moved toward more southerly aspects, but was never strong enough to support my weight on skis. Height of snow averaged around 125 cm. There were two distinct crusts in the top 10 cm or so of the snowpack with a thin layer of facets in between, a possible problem with a new load. Below these crusts, the snowpack consisted of a pencil to knife-hard slab around 75 cm thick with a few melt-freeze crusts in it, on top of 45 cm 1f-hard rounding depth hoar. Compression tests produced moderate results on the depth hoar. Extended column tests produced propagating results with moderate force on a mid-pack crust about 50 cm down. The snowpack is gaining strength here, but test results are consistent with the possibility of human-triggered avalanches.
Avalanche
No new activity observed today.