Avalanche Forecast

Moderate - Uncertainty is due to the limited number of field observations.

  

FRIDAY NIGHT: Cloudy / Strong, northwest ridgetop wind / alpine low temperature -14 / Freezing level valley bottom.

SATURDAY: Cloudy with flurries; 3-5 cm. / Light, northwest ridgetop wind / alpine high temperature -10 / Freezing level valley bottom.

SUNDAY: Mix of sun and cloud / Moderate, northwest ridgetop wind / alpine high temperature -14 / Freezing level valley bottom.

MONDAY: Sunny / Light, northwest ridgetop wind / alpine high temperature -20 / Freezing level valley bottom.

Persistent slabs are sitting on a very weak layer of surface hoar which is likely to be reactive to human triggers. Avalanches may be larger than expected due to the presence of this weak layer. Here is an example of a natural storm slab propagating wider than usual due to this weak layer. An additional recent MIN showing the same is HERE.

Note: We currently have very few observations from this region. Please consider sharing what you see by submitting a MIN report.

Southwest switching to northwesterly winds may form reactive wind slabs on a variety of aspects at treeline and above.

40-60 cm. of recent snow is sitting on a very reactive weak layer of surface hoar which has potential to surprise backcountry users by how easily it may be triggered and how wide the persistent slabs propagate across slopes. Recent avalanches on this layer have primarily been reported at treeline and below.

A second weak of layer of surface hoar from mid January is down around 70-110 cm. and is most prevalent in sheltered, open slopes at treeline and below. 

Deep persistent weak layers can still be found in the lower snowpack. These weak layers are most likely to be triggered from rocky areas with a shallow or thin to thick snowpack.

• Be aware of the potential for large avalanches due to the presence of buried surface hoar.
• Use conservative route selection. Choose simple, low-angle, well-supported terrain with no overhead hazard.
• Avoid open slopes and convex rolls at and below treeline where buried surface hoar may be preserved.
• Be careful as you transition into wind affected terrain.