Observation: Public

Observation Details

Signs of Unstable Snow

Observations

Andrew Kiefer and I snowmachined through Schriebers Meadow and up to the toe of the Easton Glacier. We saw numerous signs of old avalanche debris probably from Jan 12, including glide avalanches on a west facing slope at about 4800ft. We did not see any avalanches that occurred in the newer snow. Winds were calm throughout our travels and skies were scattered.

In Schriebers Meadow at about 3500ft we found 3mm surface hoar coating the snow. It was not present higher up. Just beneath the glacier (5600ft) we found about 4in of low density snow (decomposing forms) over a thin (3mm) melt freeze crust which was easy to punch through on feet and with snowmachines. Beneath that there was about 6in of 4F snow (decomposing forms) before reaching the 6in Jan 12 melt freeze crust. In some spots we could punch in a little with our feet, but the snowmachine track just slipped on the smooth thick crust- a challenge especially on steep hills. There was moderate wind-effect in the whole area, and we could see shiny surfaces where the recent snow had blown off the thin crust near the surface (see photo). We did not find any drifts deeper than 6in deep, and none that we saw were reactive.