Pro Field Report
Basic Information
Observation Details
Observation Date:
January 11, 2021 - January 12, 2021Submitted:
January 12, 2021Observer:
SAC - Chris Lundy (off duty)Zone or Region:
Banner SummitLocation:
Elk Creek Guard Station (6400-8400, E-S-W)Signs of Unstable Snow
Recent Avalanches?
YesCracking?
None ExperiencedCollapsing?
None ExperiencedSnow Stability
Stability Rating:
FairConfidence in Rating:
ModerateStability Trend:
WorseningBottom Line
Snowpack in this area is similar to other areas of the Banner Summit zone, perhaps a bit thinner overall in depth. Weak layer is buried 2.5' deep in mid-elevation terrain.
Advanced Information
Weather Summary
Cloud Cover:
Partly CloudyWind:
Light , WNew/Recent Snowfall:
Snowfall began around 9am this morning. 7cm HN when returned to our car at 1300.
1/11: Some scattered high clouds, but nice day with plenty of sunshine. Light winds. Temps remained cool.
1/12: Snowfall began around 9am. S1 for most of the morning, turning to S2 in early afternoon.
Avalanche Observations
| # | Date | Location | Size | Type | Bed Sfc | Depth | Trigger | Photos | Details |
|---|---|---|---|---|---|---|---|---|---|
| 1 |
Jan 5, 2021 (+/- 3 days) |
Steep/rocky solar terrain above Cape Horn rd S 7800ft |
D2 | SS-Soft Slab | O-Old Snow | N-Natural | Report |
Also, the loose snow avalanche listed above.
Snowpack Observations
Been trying to gauge snowfall patterns in the Banner Summit zone and am starting to think that the Copper Mtn area is slightly wetter than some of the other portions of this zone. However the difference is subtle, and the snowpack in this area was nearly identical in structure to areas closer to HWY 21.
HS at 6400' was 90cm, ranging to 125cm at 8000'. Slab depth range from about 2 to 2.5'. We never got very high (<8300') or very shady (E was the shadiest).
@7700', E: HS 125cm. 75-80cm slab over 12/11. Slab hardness at base was 1F+, approaching P. Weak layer hardness was 4F-. The weak layer is finally showing some signs of getting squashed but it's got a ways to go. ECTX but ECTP with a couple hard hits.
SH was fairly widespread on shady and sheltered slopes, although it seemed relatively small and not of the typical "structure" that tends to form buried weak layers. But - another thing to keep in mind with the incoming storm.
Avalanche Problems
| Problem | Location | Distribution | Sensitivity | Size | Comments |
|---|---|---|---|---|---|
Deep Persistent Slab
|
|
Layer Depth/Date: 60-80cm Weak Layer(s): Dec 11, 2020 (FCsf) Comments: Rose indicates observed terrain. 12/11 is still easily felt with a ski pole. |