North Columbia

A widespread natural avalanche cycle is forecast to continue on Tuesday. Travel in avalanche terrain is NOT recommended.

High -

NOTE: Freezing levels are forecast to remain elevated overnight throughout the forecast period. This will significantly increase the impact of day time warming on the snowpack.MONDAY NIGHT: Clear / Light, northwesterly winds / Alpine low 4 / Freezing level 3000 m.TUESDAY: Sunny / Light, southwesterly winds / Alpine high 8 / Freezing level 3000 m.WEDNESDAY: Sunny / Light, southwesterly winds / Alpine high 8 / Freezing level 3000 m.THURSDAY: Sunny / Light, southwesterly winds / Alpine high 6 / Freezing level 2600 m.

On Sunday, a widespread loose wet avalanche cycle to size 3 and numerous size 3 persistent slabs were reported on solar aspects at all elevations. A natural avalanche cycle is expected to continue on all aspects and at all elevations on Tuesday.

40-60 cm. of well settled snow has created a cohesive slab sitting on a pile of facets (sugary snow), as well as a crust on sun exposed slopes. Natural avalanches on this layer are expected to continue.At lower elevations below treeline, a weak layer of surface hoar (weak, feathery crystals) buried in mid-January can be found approximately 70-120 cm. deep and may be combined with a crust on south aspects. The current warming event may awaken this layer, resulting in large, destructive avalanches. Steep cutblocks and large open glades at lower elevations are the most likely places to trigger this layer. Smaller loose wet avalanches may "step-down" to this deeper layer.The lower snowpack is generally considered to be strong in most areas; except for rocky areas in the alpine with a shallow snowpack where multiple days of intense sunshine and warming could trigger sporadic very large avalanches running to valley bottoms.