Be observant to the affect of the warm temps and sun today in the alpine today. Use caution in terrain where even a small avalanche could have high consequences.
Weather Forecast
The dry spell due to a high pressure continues. Models show a significant temperature inversion inplace today with alpine temps above 0 while the valley bottoms will stay chilly at -10. Ridge top wind will be N'ly 20-30kphKeep in mind it's early winter and it gets dark early! Factor extra time into your day to be back at the parking lot before dark
Snowpack Summary
Cold temps in the valley bottoms are preserving last weeks snow and causing surface hoar growth and surface facetting. 15-25cm of lower density snow sits on a well settled mid pack. Moderate ridge top winds and stronger localized downflow has loaded alpine features with thin wind-slab and created a variety of wind affected surfaces lower down.
Avalanche Summary
Yesterday there was evidence of loose, solar triggered avalanches. They were up to size 2 and were occurring from steep, rocky terrain exposed to the sun. This week we have also had two skier triggered avalanches from high alpine terrain features, both were sz 1.5 windslabs. There have also been glide crack releases observed below treeline.
Problems
Loose Dry
Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.