Main concerns: Loose Wet, Wet Slab, Cornice Fall.
Summary
Travel & Terrain Advice
Avoid exposure to all avalanche terrain during the warm temperature spikes accompanied by rain events over this forecast period. The thin/shallow early season snowpack will quickly lose stability as temps climb and rain saturates the snow.
In all but the alpine, the snow levels are still low, so be wary and on the look out for open creeks/holes and rocks/stumps etc lurking just below the surface.
Due to limited obs, spend a good amount of time doing your own snowpack observations and if unsure/unableā¦ as usual avoid avalanche terrain.
Avoid wind loaded slopes where trigger-able slabs maybe (NW-NW aspects).
Avalanche Summary
No avalanche data/observations are currently available due to minimal field time (as it is the beginning of the season teams have not gotten out and about) and there has been limited visibility. During this forecast period, one can certainly expect to find evidence of a widespread loose wet avalanche cycle in the alpine and at treeline as a result of the big rain event (at all elevations) that happened Thursday Dec 13.
Snowpack Summary
A thin early season snowpack down low (below treeline). Zones of deep snow are found in wind loaded lee pockets in the alpine and treeline. Rain has saturated shallow areas right down to the ground and the majority of lower below treeline terrain is below threshold (to shallow to have avalanches of significant size). High winds have resulted in some cornice development in the alpine and treeline.
Snowpack Details
Surface: wet snow from Thursday nights rain event with new moist snow arriving Friday. Upper: rain saturate snow with a few thin melt freeze crusts. Mid: rain saturated snow from previous snow events. Lower: large crust from early season snow with a potential failure layer (of still dry snow treeline and above)mid crust, all bonded poorly to ground.
Past Weather
A large rain event Thursday night has saturated the thin early season snowpack. High winds during prior snow events has transported significant amounts of snow in the alpine and treeline elevation bands.
Weather Forecast
Multiple rain and snow events as temps and freezing levels fluctuate with steady moderate to strong SW to SE winds.
Friday - Heavy rain and snow with strong winds during the day at all elevations. Temps and freezing levels drop overnight resulting in light to moderate snowfall.
Saturday - Light-moderate snow fall in the morning with cold temps (-2 to -5). Snowfall increasing to moderate mid day then heavy overnight. Winds remaining moderate to strong SW to SE. Small reprieve between two big warm weather events.
Sunday - Heavy snowfall continues into the morning potentially changing to moderate to heavy rain around noon. Winds remain moderate to strong.