Southern San Juan
AvalancheAnonymous · Mar 23, 2020 · Southern San Juan
Weather
Mild temps for the most part all day, snow began afternoon and continued off and on with some squalls more intense than others, accumulations were light. Winds were mostly calm below treeline with moderate gusts on ridge lines above.
Snowpack
Found a very similar snowpack structure to that found throughout the La Platas on NE facing slopes and the north half of the compass I general, the fresh snow from the weekend has settled into a 2-3 foot slab overlying weaker, faceted snow grains. The new snow on southerly facing slopes we travelled on below treeline had developed a very easily breakable surface crust with a dense slab underneath. Also observed a very isolated pocket of a hard wind crust, capped with a 4-6” fresh and very soft wind slab just below a ridge line on a NE facing slope just above treeline.
Avalanche
Observed one natural avalanche on an east facing slope, above treeline, just below the rocky ridge line between Burwell and Gibbs peaks. It was difficult to see from our perspective exactly when it released, how deep it broke, and how far it ran but it looks to have only slid on one of the interfaces between slabs of recent storm snow rather than further down on the deeper, more concerning faceted layers, and the crown was at least 15 meters wide. The slide was most likely initiated during one of the more intense periods of loading from Wednesday-Friday. The crown is a little bit hard to make out in the picture but is most pronounced on the lookers right side of the photo, just underneath the large cliffs.