Snowpack

Observation: Powder Mountain Backcountry

Evelyn, Nichole, ButchOgden
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Observation photo 1

Quick report

Aspect
North
Elevation
2652 m
Slope Angle
30°

Goal of the day was searching for old faceted pre-Thanksgiving snow. Looked at two higher elevations, northerly facing slopes. We found the facets, but the layer is very thin - maybe averaging 2 to 6 cm thick, up to 10 cm in a few places. First two ECT tests in two different places - no fracture. Third test, in the same pit as an ECTx - we got an ECT12. There was no crust in the snowpack.

My overall feeling is on the high elevation, northerly facing slopes, the basal facet layer is so thin, that it's not continuous over the terrain, instead being broken by rocks and vegetation. I think there are only isolated places - above about 8500', northerly facing, with very smooth ground like rock slabs or grass - where you could connect a large enough area of the depth hoar for a slide to release. Of note - we have few observations from the 9,000' to 9500' band in the Ogden area mountains, where the depth hoar could be a little more continuous.

Second snowpit profile above. Below, well developed, striated facets at the ground.

Snowpack

Instability Comment
<p>With so much new light density snow, I would expect sluffing on steep slopes. A few layers identified 30 and 40 cm down that failed with compression tests seem to be new snow instabilities, that should continue to strengthen. Though not in the forecast, if winds pick up there is lots of snow available for transport, and the danger could spike fast.</p> <p>Other thoughts for the future - the low density surface snow will be able to facet rapidly if we have cold, dry weather; and it will be worth keeping an eye on the shallower mid to lower elevation slopes for snowpack weakening.</p> <p>See comments below snow profile.</p>

A few more inches of low density snow in the last 24 hours are icing on the cake.  They're sitting on mostly right side up snow that accumulated during the last 4 days.