Northern San Juan

Avalanche

Chris Bilbrey Ann Mellick · Apr 16, 2021 · Northern San Juan

Weather

Cool, spring-like day with abundant sunshine and light winds. Temperatures remained below freezing at pass level by early afternoon. However, the new snow baked down pretty quick from the influence of a April sun.

Snowpack

We found around 5 inches of new snow near treeline and drifting up to 8 inches deep on the lee side of terrain features in the alpine. The new snow was not slabby (mostly 4F to 1F-) and bonding well to the firm old, snow surface. Small sluffing with morning sunshine in steep, rocky terrain was the most notable fresh avalanche activity observed. We were able to get a few small sluffs to move downhill with ski pressure on a west-facing slope, but they did not travel far and were confined to areas of the slope steeper than about 35 degrees. By the time we descended lower in elevation mid-day, the snow was quickly setting up and becoming moist. While descending a north-facing slope around 10,600 feet at 1 pm, we easily punched through to the ground in wet, rotten snow. This occurred despite last night's strong freeze and confirms how weak the snowpack has become at lower elevations and even on northerly aspects.

Avalanche

Several small (D1) Loose Dry avalanches on east to south-facing slopes above treeline from morning sun. None traveled far or entrained snow below the new/ old interface. Lots of older wet snow avalanches from around April 4 or 5.