Northern San Juan
AvalancheAnn Mellick Chris Bilbrey · Mar 5, 2021 · Northern San Juan
Weather
It was a sunny, mild and calm San Juan day. Most alpine weather stations hit near or above freezing today.
Snowpack
Recent storm snow was not sufficient to greatly stress the lower snowpack. We observed good bonding at the new/ old interface on multiple aspects. On an east aspect at treeline, we found a reactive storm layer in deeper drifts that will most likely settle out in the coming days. Today's warm temperatures and strong solar input quickly affected surface snow on sunny slopes making it moist, heavy and squishy. This was most pronounced below treeline and surface warming observed at all elevations. Digging deeper in the snowpack revealed a lingering strong-over-weak snow structure. We found these conditions on most slopes, but this setup continues to be more difficult to trigger in stability tests. As we transition further into spring, buried weak layers could rear their ugly heads as water moves deeper in the snowpack.
Avalanche
Lots of roller balls and D1 wet loose activity on sunny slopes, especially in steep rocky areas. All limited to the new snow and none triggered any slabs.