Clear Brook Cirque, W facing slide.

Quick report

Cracking

isolated

The snowpack in the outer Pemi is much thinning and appears to be undergoing change from the long period of cold temps. While this area is outside the forecast zone, it seemed like an observation from this side of the Whites could be of value to anyone who explores out here. And with limited ski traffic in this part of the range, hopefully this can contribute to the broader understanding of trends in this snowpack and how they compare/contrast to the Presidentials The W facing slide was mostly P hard windboard once we ascended to the more open part of the path. We observed old avalanche debris and a faint crown line on the right side of the slide (see avalanche summary). Near the top of the slide, we observed a small pocket of 1F wind slab that was cracking on faceted crystals. This pocket was very small and isolated but could exist elsewhere in the range beneath larger slabs with more connectivity. I would be interested to know if this later resulted in the avalanche that we saw evidence of.

Weather

Air Temp

N/o

Cloud Cover

overcast

Wind Loading

none

Rain Elevation

N/O

Recent Snowfall

None

Snow Avail For Transport

none

Sky condition: OVC, Wind: C, BLSN: None, Precip: No. Temp: N/O

Snowpack

The snowpack in the outer Pemi is far less developed than the Presidential Range or Crawford Notch. Below 2800 feet there is aprox 60 cm of snow cover. The snow is for the most part unconsolidated powder sitting above an ice crust just above ground level. The snow is beginning to facet and in certain areas we were able to break through the crust. Once we gained the West facing slide. It was clear that despite being below treeline, it was very exposed to the wind and we found ourselves traveling on firm wind board, with the entire right side of the slide being firm ice crust and rocks exposed by the avalanche. Near the very top of the slide we observed an undisturbed pocket of snow with a softer old wind slab cracking on facets. While this pocket was isolated, in a slide that was not affected by a previous avalanche, I wonder if you would see more evidence of this.

Avalanche

Size

D1 R2

Type

U

Aspect

W

Trigger

NO

Elevation

3440 ft

Upon first glance this appeared to be a serious of loose wet roller balls from a previous day of sun, however they were slightly buried and a very faint crown line was visible across the top of the slide. This area is not visited often, so it’s safe to assume this was naturally triggered. While it’s mostly likely a storm slab from the 1/26 storm, it’s impossible to know for sure. The bed surface was a thin melt freeze crust, just barely covering ground. The cracking we were observing on facets higher up in an isolated pocket not impacted by the avalanche are curious. I wonder if avalanche failed on the crust, or facets above the crust that were blown away by the wind in the week that followed. While we can’t draw any definitive conclusions, I thought this was an observation worth submitting.