Observation: NWAC Observer

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Weather Summary

Light rain in the am, tapering by 1 pm. Clouds began clearing from X/OVC in the am to BKN by the afternoon.

Avalanche Observation Comments:

Glide cracks and glide avalanches were observed on many steep rocky slopes. In addition to the glide cracks, we found widespread cracks in the snow surface, probably resulting from the snowpack adjusting to the rain.

Loose wet debris was observed on specific steep terrain.

We could see debris from what looked like a very large wet avalanche on the south side of Alaska mountain. We could not make out if there was a crown, or determine if this occurred in the last 24 hrs.

Snowpack Observations

We found wet surface snow on top of a breakable crust. This crust varied in thickness but was present up to at least 4,500 ft. This crust was not supportable to skis.

In the trees, the snow was generally firm and tree-bombed. Little snow remains in the trees at this elevation.

At 4,200 ft, we found an average height of snow of 200 cms. At the surface, we found a 3 cm pencil hard melt-freeze crust. This sits on top of about 10 cms of moist fist-hard rounding grains. At 16 centimeters down from the surface, we could identify a thin crust remaining from the 1/7 AR event. This crust seems to have broken down significantly with the most recent rain event.

Beneath the 1/7 crust, we found increasing density snow, transitioning from moist to dry at around 50 cms from the surface.

Shovel shear tests highlighted several density breaks lining up with the crusts and the water percolation. These layers were unreactive in other tests.

Avalanche Problems