Pockets of MODERATE avalanche danger remain near treeline and above treeline on NW-N-NE-E aspects on slopes 35 degrees and steeper due to lingering wind slabs. For all other areas, avalanche danger is LOW. Rain on snow may create isolated areas of loose wet avalanche activity, possible on any aspect on slopes 37 degrees and steeper.
Continued wind transport and subsequent wind loading has allowed for wind slabs to linger in near treeline and above treeline terrain. These slabs are high density and difficult to trigger, but human triggered avalanches remain possible in some areas on NW-N-NE-E aspects. Snowpack failure may occur anywhere from 6 inches to several feet deep within the recent new snow.
If snow levels rise above 7,000' today or tonight, areas of rain on new snow will likely occur. This will allow for the possibility of small loose wet avalanches on any aspect, mainly in areas below 8,000'. Steep slope angles of 37 degrees or greater will likely be required for loose wet avalanches to initiate. Only the top one to three inches of recent new snow is expected to become involved, but deeper snow may become entrained in areas where crust does not exist within a few inches of the snow surface.
Observations made yesterday on Silver Peak (Pole Creek area) revealed minor evidence of lingering snowpack instability. Below treeline, ski cuts, hand pits, pole probing, and general observations did not reveal any signs of unstable slabs. Ski cuts triggered minor roller balls and pinwheels as well as one very shallow sluff that entrained 2 inches of new snow above near surface melt freeze crust. Near and above treeline, wind slabs lingered and southwest winds were observed transporting snow onto leeward aspects. Stomping on wind loaded rollovers elicited minor cracking, but did not produce wind slab failures. Snowpit tests indicated that the bond between the recent wind slab and the snow layer below continues to gain strength.
Informal observations made yesterday on snowmobiles in the Blue Lakes area (Carson Pass) noted similar conditions with blowing snow above treeline adding to existing wind slabs and no observed evidence of instability below treeline.
