Quick report
- Collapsing
- isolated
We experienced 2 small collapses that involved stiff drits of windblown snow; it did not seem like these were happening on the 1/6 interface, maybe 2/1 or a mid-storm interface from early Feb.
Weather
- Snow Avail For Transport
- moderate amounts
Cloud cover decreasing into the afternoon, allowing for plenty of direct sunshine from 1300 to sunset. Winds were generally light, with periods of steady upper end of moderate winds blowing out of the W in exposed upper elevation terrain. Winds transported snow when blowing harder, but mostly they weren't moving snow. There is still a good bit of soft, transportable snow at the surface, but we'd probably need to see an extended period of stronger winds to really put a bunch of this into motion.
Snowpack
Continuing to monitor surfaces in advance of a return of precipitation. As usual, we are alternating between 1 of the 3 general options here in central Idaho: weak layer formation, slab generation, and melt. We find ourselves in the weak layer formation phase. Solars and solar margins have relatively thin, breakable crusts that are commonly accompanied by facets (lots of RadRx here, and in obs). On shaded slopes, generic FCsf are developing. These don't look terrible, but could certainly be a player in the short term. A few batches of SH have been deposited since snowfall stopped. The wind is knocking some of this down, the sun is wilting some of it, if this becomes problematic it is likely to be most problematic in sheltered, shady terrain. I have observed SH up to 10,000' on the Salmon side of the pass and up to 10,500' on the Big Wood side.
2/1 interface is visually dramatic, and has some faceting present of either side of the crusts that exist at this interface. My recent snowpits are not pointing to clear issues at this interface, but the number of avalanches that have occurred on this layer, and the general synoptic weather patterns that formed this layer, point to the potential for this to become a specific problem in areas where the slab is thick enough and the weak layers are well developed. Even where this bond is strong, the presence of this crust will help surficial avalanches run quickly downslope.
Avalanche
- Size
- D3
- Count
- 20
- Aspect
- NE
- Trigger
- N
- Elevation
- 9800 ft
We observed numerous avalanches, many of which were reported by Brooke in her ob from 2/10. There were a number of large avalanches on the Big Lost/Trail Creek side of the headwall. Many of these broke hundreds and hundreds of feet wide. Most activity seemed to involve 1/6, though some slides look to have stepped down to the 11/30 interface. Near some crowns, you could make out small areas where the 2/1 interface flanked out and released above the 1/6 surface.