Quick report
- Red Flags
- Wind Loading, Poor Snowpack Structure
Snowpack
- Instability Comment
- <p>Winds were actively transporting snow throughout the day, especially along the ridgelines. The interface has a lot of density changes, including graupel layers. I’d expect those wind drifts to keep growing along ridgelines and catch points, especially as we move into the system tonight with sustained elevated winds and heavy new snowfall on the way. We could see shallow wind slabs failing on the new snow, graupel interface at first, then stepping down more deeply, either on top of the crust or into the older faceted snow below it.</p> <p><em>Growing small cornices and active drifting in Upper Silverfork</em></p> <p>The poor snowpack structure is still out there. We dug around in Hideaway Park, trying to find a spot just below 10,000 feet where the crust interface might be a bit thinner, similar to what we’ve been seeing in Hidden Canyon and around Sunset Peak. On a northeast aspect near 9,990 feet, we found a 100 cm snowpack with new snow and decomposing fragments sitting on about 60 cm of stacked crust interfaces and facets. The main rain crust itself was only 5 cm thick and pencil plus in hardness, with another 5 cm of mixed melt forms underneath it.</p> <p>The crust was supportable and honestly a pain to saw through, still solid, but noticeably thinner than what I’ve seen in a lot of other places. The snow below the crust interface was dry and weak, especially near the ground. We didn’t get any results outside of the surface snow with either ECT or CT tests.</p> <p>What does this say? Mostly that the variability slope to slope is huge. Even at similar elevations and on similar terrain features, this is rocky upper elevation terrain, and it’s been tough to pin down much of a pattern. My main concern though is that with additional load and colder temps, we may start seeing more avalanches either stepping down to this layer or failing on it directly.</p> <p><em>Pit profile - Upper Hideaway - NE Aspect - 9907' - ECTX </em></p>
The snow surface was made up of 1 to 3 inches of new graupel sitting on the old snow surface. Even though winds were clearly transporting snow, we didn’t see much sign of wind effect on the surface where we traveled today. No cracking, no collapsing.
The big surface takeaway was the graupel. It was super easy to push around and readily entrained on steep slopes. Riding was surfy, but you could still feel whatever was underneath without much effort. We found a crust on southern aspects and softer snow on northerly aspects.
Graupel of various sizes on the surface