Quick report
- Cracking
- specific
We investigated mid and upper elevation slopes in the Northern Swan today (2/27), where up to a foot of snow fell over the past few days. Moderate winds from the SE left reactive wind slabs on NW-W aspects at upper elevations.
- Small wind slabs were reactive to the weight of a rider with shooting cracks traveling several feet on NW aspects. There was active snow transport across the drainage adding to previous developed cornices.
- We found a persistent weak layer in 3 snow profiles (N-NE-E) buried up to 100 cm. We didn't have any propagation on this layer in our ECT tests. A PST on a N aspect propagated thru the full block at 68 cm.
Our mindset for the day was assessment. With new snow and moderate wind speeds from various directions across the forecast area we avoided slopes over 30 degrees and had a great day in the snow. Light to moderate snowfall in the morning yeilded to scattered clouds with the sun making an appearance by mid-afternoon.
Wind slabs cracked and failed along W-NW ridgelines above 6500'. We avoided slopes over 30 degrees where a loose dry problem most likely would have existed.Weather
- Air Temp
- 23
- Cloud Cover
- broken
- Wind Loading
- moderate
- Rain Elevation
- n/a
- Recent Snowfall
- 30
- Snow Avail For Transport
- moderate amounts
Intermittent snow showers (S1) throughout the day with gradual clearing by early afternoon. By 2pm shifted to scattered clouds with patches of blue sky.
Snowpack
We found 30 cm of recent snow on top of a right side up slab. This slab is still sitting on a stout crust that was buried in early February. Light to moderate winds were transporting this recent snow and added to wind slabs forming on W-NW aspects. Some of this may have been a result of terrain features funneling wind onto atypical slopes.
Snowpit data:
- Northerly aspect at 6600'. HS 168 cm. ECTX. PST 68/100 END.
- East aspect at 6620'. HS 181 cm. ECTX. CT 23 on storm/gaupel layer.
- NE aspect at 6700'. HS 173 cm. ECTN26 down 30 cm.