Southern San Juan
AvalancheChris Bilbrey · Apr 18, 2023 · Southern San Juan
Weather
High clouds and steady southwest wind in the morning. Skies cleared late-morning with mostly sunny skies for the remainder of the tour. The wind never relinquished its fury, and another wave of desert dust arrived around 3 PM.
Snowpack
Another solid surface re-freeze last night at all elevations made for very supportive travel across aspects. Clearing skies today allowed surfaces to soften, but the steady wind contributed to a slow, methodical warm up. By the afternoon, leeward-facing terrain got softer than windward, sunny slopes. All in all, we found only an inch or two of softening above 12,000 feet, that increased to 3 to 4 inches near and below treeline. When booting above treeline, the deepest part of steps ranged 4 and 6 inches deep. Once we descended to around 10,000 feet in the afternoon, boot penetration increased to around 8 inches. When probing across easterly-facing slopes at upper elevations, we found fairly homogenous layering in the top 50 to 70 cm consisting of melt forms and crust. Northerly alpine slopes remain a mixed bag of wind-texture, smooth hard surfaces, and leftover softer snow from snowfall on April 14. Below about 9,500 feet, the snowpack is further along in its spring transition. The snowpack there looks tired, worked over, and wet snow hazards seems unlikely. Isolated places below steep cliffs or in gullies with running water below are the spots to avoid at low-elevations. Creeks and waterfalls continue to open up, but a lot of viable snow bridges still exist in most drainages.
Avalanche
Continue to document large Loose Wet avalanches and Wet Slab avalanches that ran between 4/10-13 during the major warm up. No new wet snow activity from the more recent warm, sunny days.