Sawatch

Avalanche

Luke LeMaire Coleman Kane · Apr 15, 2021 · Sawatch

Weather

The weather today was variable and ever changing. There were periods of light snowfall and moderate southerly winds, followed by a break in the clouds and warmer temperatures. In the afternoon, the temperature was hovering near freezing with mostly cloudy skies before graupel rolled in around 2:45.

Snowpack

Above treeline on a north facing slope, snow heights varied drastically from nearly to the ground up to 3 meters in drifted areas. A strong slab over a persistent weak layer was found in this terrain, but this structure was discontinuous, even over short distances. Near treeline on the same aspect, snow depths averaged 150cm. We found that there is still a slab over weak layer structure, but the only weak layer is depth hoar and is difficult to affect. This stratigraphy was consistent across the terrain. In the afternoon below treeline we observed a variable crust, which once warmed, did not support a skier. We did have a collapse on a gentle slope from a thick crust above wet snow grains to the ground. It propagated about 15 feet below one skier and 20 feet above an adjacent skier.

Avalanche

Saw evidence of an old wet loose avalanche on the northeast shoulder of Mountain Boy Peak. WL-N-R1D1, east aspect , above tree line. It looks to have started below a cliff band. On the drive up we saw wet slab debris and crowns in some of the couloirs coming down from the Twin/Rinker Peaks area.