Northern San Juan
AvalancheAmy Pertuz · Dec 30, 2021 · Northern San Juan
Weather
Moderate temps in the 20s with scattered light snow showers and moderate to strong winds throughout the day out of the SW. Blowing snow was mostly moderate. I stayed out of the alpine. Precipitation picked up late afternoon, but totals for the daytime were around 5" on RMP side and 9" Canyon Creek side. Visibility and drifting obscured much chance for observation in the alpine.
Snowpack
On Northerly below tree line slopes, HS ranges from 120cm to 160cm and yesterday the surface on these slopes showed evidence of light wind drifting due to yesterday's strong SW winds. The basal facets range fomr 35-45 cm and are 3-4mm .The midpack on these BTL northerlies (spanning between 12/6-12/24 interfaces) is generally 4F on NW aspects and mostly 1F on N and NE and N aspects. NW aspects less reactive in large column tests (ECTX on the 12/6 interface at 40cm on a BTL NW aspect with a HS 158cm) than N and NE aspects which are still propagating in large column tests, but with increasing test scores (ECTP23 on the Dec 6 interface 44 cm from ground on a N aspect BTL with a HS 162 cm and a stouter !F slab in the midpack) . A fist hard layer in the middle of last week's storm snow was sandwiched between two denser layers and could become an issue with future loads. A lot of depth has been added to the snowpack in the last two weeks! Recent storm snows are well bonded. No cracks or collapses today, prevalent just a few days ago.
Avalanche
No new avalanches seen today with occasional opportunity for viewing.