Aggie

My goals today were to hone in on northerly aspects near and above treeline, as well as to monitor warming. 

See either the snowpack section or the TL;DR at the bottom of the snowpack section for my wormhole on northerly terrain.

We found soft turns on southerly aspects and on low-angle, sunny terrain beginning around 12 pm. Things were slow to soften today, with partly cloudy skies limiting solar warming and light winds helping to keep the temperature down. By 1 pm, low-angle, low-elevation northerlies were just beginning to soften at the surface.

Coverage continues to diminish, and access to the southerly side of the Morrison Col looks to involve a walk across a lot of dirt.

Surfaces were firm to start the day, and ski crampons were a needed item in the pack.

No signs of instability.

I focused on north-facing aspects at mid- and upper elevations to gauge how the upper snowpack has been affected by warming since 2/24. Northerlies have dried out since our week without a freeze, ending 3/3. I dug a few holes today, all on north or northeast aspects. One at ~10300', one at ~11200, and another quick peak at 10600'. While they all had signs of melt in the upper layers, they also had a few differences. 

• ~10300' had layers of refrozen meltwater, melt forms, and refrozen melt freeze crusts in the top 25cm. This location had a more extensive warmup, but meltwater may not have percolated down to the 2/10 interface. A dense layer of small rounds lived under the top 25cm, with small (1mm) rounding facets existing below (2/10). The 2/10 interface showed signs of healing since it had been buried, with a hardness of 1F and small facets.
• ~11200' had obviously been less impacted by the 2/24 warmup. The surface had a few cm of wind-packed snow resting on a cohesive Pencil melt-freeze crust. This cohesive layer from 130-115cm appeared to have become denser from the 2/24 warmup, but it did not contain refrozen meltwater or show signs of any true drainage. Below the 15cm melt-freeze brick, a 35cm layer of small rounds existed above the 2/10 interface. The facets in 2/10 at this higher location were larger (2mm) and, while still relatively firm  (1F), had a much more intact structure than those at 10300'. 
• To really muddle up any continuity in the impact of warming in the upper snowpack, I popped my head into a hasty hole at 10600' on a northeast aspect. The surface had an ice lens (presumably from a quick spit of isolated rain showers around 3/1) capping another 30cm melt freeze crust complex. Small, dry rounds existed 30cm down. I did not dig to 2/10 at this location because my shovel may have cracked in half while trying to get through the surface brick.

 

TL;DR

Lots of variability. But, northerly aspects near and above treeline in the Convict to Aggie area have an entirely dry snowpack below our upper melt-freeze craziness. 2/10 is still easily discernible, but is composed of harder (1F) rounding facets beneath small, compressed rounds. We have a fine-grained slab interfacing with coarse, rounding facets.