Quick report
- Red Flags
- Recent Avalanches, Wind Loading, Poor Snowpack Structure
- Red Flags Comment
- <p>The southerly winds were transporting significant snow on all the upper elevation onto NW, N, N and NE facing terrain. Poor snowpack structure noted at 9700 feet on north aspects with the 1/5 interface (pre-frontal) having well developed small facet grains. Hasty pits and hand shears were yielding easy shears 50 to 60 cm down. The dense snow from the weekend appears to be consolidating and becoming a more cohesive dense/stiff slab. Avalanche activity (D2) from the weekend observed in upper Mary Ellen Gulch in Silver Creek Bowl as well as 4th of July Bowl. </p>
Snowpack
- Instability Comment
- <p>See above, and with the winds appearing to not be loosing strength, this problem may be increasing overnight. </p> <p>Persistant Slab concerns appear to be possible at three distinct layers. The previously cited 1/5 pre-storm interface appears to be the most likely. There is also the mid December interface that may be lingering in some shallower snowpack locations as well as basal facets in steep/thin/rock/shady snowpack areas. </p>
Mondays winds created dense surface and sub-surface snow conditions, and the warm temperatures on Tuesday combined with these windy conditions to help bring on at least 25% settlement in the abundant snow fall from the weekend. HSN has now shrunk to 50 cm at 9500 feet in shady terrain. In all but except the most sheltered terrain, when turning you were only carving into tghe upper 15 cm. In more exposed terrain the snow surface was dense, wind packed and one finger to pencil hard. Afternoon solar continued to warm the snow surface on S and SW aspects with slope angles 25 degrees and greater, yet there didn't' appear to be any new significant wet loose activity in the upper elevations.