Northern San Juan
AvalancheJeff Davis Chris Bilbrey · Jan 24, 2020 · Northern San Juan
Weather
Felt like the warmest day in quite sometime. Very little wind observed besides on ridgelines. Clear skies for most of the day with light cloud cover building during the afternoon hours.
Snowpack
Tuesday & Wednesday a winter storm produced 12" of snow and 0.9" of SWE in the Red Mountain Pass area. Thursday, strong northwest winds redistributed the storm snow onto leeward slopes. During today's tour we were surprised to see how little slab there was in the upper snowpack. Pockets of drifted snow were up to 18" deep, but did not crack or avalanche on test slopes. So even with yesterdays small natural avalanche cycle triggered by wind-loading the soft slabs we observed today were less reactive. Another observation was the recent solar input. Strong sun and warm temperatures were creating a crust on sunny slopes. Any new snow on sunny slopes quickly settles and felt moist at lower elevations. The snow remind dry on shady slopes. No cracking or collapsing.
Avalanche
Thursday strong winds and ample low density snow triggered a small storm snow cycle. Most avalanches were observed on east to south-facing slopes, but there was also an avalanche on a north slope below a rock band in the Commodore area. Friday, warm temperatures and ample sunshine also triggered a small loose cycle on sunny slopes.