Aspen
AvalancheMatt Huber · Apr 16, 2020 · Aspen
Weather
Heavy snowfall during the entire trip with rates of 1-2 inches per hour. Winds were light near and below treeline with evidence of previous wind loading. Very little slab development until I reached the exposed alpine terrain where winds were drifting snow onto easterly slopes. By 5:00 in the evening storm totals were close to 16" at 10,500 feet.
Snowpack
Near and below treeline, storm slabs did not show much reactivity until totals topped the 12-14 inch mark, even then they remained small. I would expect the sensitivity to increase as the storm snow settles into a denser slab. Above treeline, there was zero visibility and stayed on low-angle terrain. Winds were easing by late afternoon but obvious signs of scouring and loading exist from earlier. On a northeast-facing slope near treeline, the new snow was not bonded especially well to the old surface. At this elevation though, no slab existed in the storm snow and produced easy, non-propagating results. Extended column tests did produce hard, propagating results on a facet/crust layer 70 centimeters from the surface.
Avalanche
Small natural storm slab avalanches began to release on very steep, unsupported slopes once storm totals topped 12-14 inches.