Quick report
- Cracking
- specific
- Collapsing
- specific
The Banner Summit Zone has received a healthy dose of snow over the last week. At valley bottom, this recent snowfall accounts for a significant proportion of the snow on the ground. Above 8000' a layered season snowpack has taken shape where old snow near the ground is soft and weak. Snowfall since Wednesday has added significant weight to the snowpack and has bonded poorly to the old snow that fell last weekend. This was exhibited by propagating test results in stability tests.
Along ridgelines, moderate winds have transported recent snow into thin drifts that collapse and crack under the weight of a person. Snowfall returned in the early afternoon, and increasing winds were actively transporting snow into dense drifts along ridgelines.
Weather
- Air Temp
- Low 30s and dropping through the day above 8k
- Cloud Cover
- overcast
- Wind Loading
- moderate
- Rain Elevation
- 7000'
- Recent Snowfall
- 50-60 cm since 11/20
- Snow Avail For Transport
- moderate amounts
Cloud cover increased and skies were overcast by 11 AM. Snow rain mix began at 1030 AM, with intermittent periods of snowfall above, 7500'. Southwest wind began light before increasing to moderate. Temps began warm in the morning but fell through the day.
Snowpack
Snowfall over the last week makes up well over half of the snowpack on many slopes below 7500'. Old snow near the ground is weak, moist and faceted. This old snow has been compacted by the weight of recent storms and is only 5-10cm thick in many areas. Snowfall over the last week has bonded well to the old surface at these elevations.
Above 8000' a seasonal snowpack has taken shape ranging from 80 to 120cm deep. On an east facing slope at 8300', 10-20cm of October snow near the ground is faceted but moist and trending towards rounding. Above this is a thin (2cm) crust-facet combo that was unreactive in stability tests. Mid-pack the interface between the snow that fell last weekend and this recent storm is a thin layer of small grain facets that produced propagating results in stability tests (ECTP 23 & ECTP 22), 65cm from the surface (HS 120).
