Rapporto rapido

Arctic Valley

Avalanche.org observerChugach State Park
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Quick report

Collapsing
widespread

This was a field day with the Alaska Avalanche School. We toured in three groups up towards Gordon Lyon, observing snowpack conditions and digging snowpits. On the tour up we observed widespread collapsing on a layer o f buried surface hoar under a melt freeze crust 5 cm deep. These failures were small, producing a "hissing" sound rather than a heavy "whomph". We dug snowpits around 3500 feet on NE and SE aspects. In our snowpits this surface hoar layer failed on isolation during CT tests (CTV) and produced mostly ECTN results, although at least one ECTP was seen on this layer. The rest of the snowpack was largely unreactive, although we could get failures on the depth hoar at the bottom of the snowpack when we wailed on the shovel at full strength. During the day we saw significant snow transport as the winds built through the day. Valley winds were coming out of the east.