Avalanche Forecast

Moderate - Wind effect is extremely variable

Arctic air continues to be entrenched in the Purcell region. The pattern will start to shift Thursday to a zonal flow, allowing Pacific frontal systems to make way into the Interior early next week. Little change for the weekend.Thursday/ Friday/ Saturday: Mix of sun and cloud with a slight alpine inversion bringing temperatures near -15 and valley bottoms -20.  Ridgetop winds light-moderate from the West.

On Tuesday, numerous wind slabs up to size 1.5 were reported. A couple of these occurred naturally due to the previous wind event and the others were easily triggered by the weight of a person. On Thursday, recently formed wind slabs may still be reactive to human triggering. With the winds switching directions, wind slabs should be expected on a variety of aspects.

15-30 cm of recent snow has buried a variable old snow surface which consisted of wind scoured surfaces or old wind slabs in exposed terrain, surface hoar in sheltered terrain, and/or widespread faceted old snow. Recent moderate winds from a variety of directions is expected to have redistributed some of this new snow in wind exposed terrain. The layer of facets from mid-December is still reactive to snowpack tests in isolated areas but is generally considered to be dormant during this period of cold, dry conditions. It will be important to watch this layer reacts during the next storm or period of warming.