South Columbia

New snow and wind on Friday and overnight is expected to create touchy storm slabs that are reactive to human triggers. Be especially cautious in wind exposed terrain at treeline and above.

Low - Due to the number of field observations

FRIDAY/NIGHT: 5-15 cm new snow expected by Saturday morning / Moderate to strong southwesterly ridgetop winds.SATURDAY: Mostly cloudy with isolated flurries / Moderate southwesterly ridgetop winds / Freezing level around 1000m.SUNDAY: Mix of sun and cloud / Light northwesterly ridgetop winds / Freezing level valley bottom.MONDAY: Mix of sun and cloud / Light to moderate westerly ridgetop winds / Freezing level valley bottom.

On Thursday, numerous small (size 1) human triggered storm slabs were reported on all aspects at treeline and above in this region. We currently have very limited observations in this region. Please submit your observations to the Mountain Information Network (MIN).

Between 30 and 45cm of new snow has fallen in the past few days. I'd expect reactive storm slabs to exist in wind-exposed terrain or in places where the recent storm snow has a weak bond with a crust which formed in late November and can be found around 60cm below the surface.Another feature in the snowpack is a 3-5 cm thick crust which was formed around Halloween and can be found approximately 100cm down at treeline elevations. This layer is generally thought to be stubborn to trigger; however, it may be worth investigating if your travel plans involve large triggers on big, steep, unsupported terrain.The depth of the snowpack varies greatly with elevation. Recent reports suggest the average depth is 200+cm in the alpine, 100-180cm at treeline, and decreasing rapidly below treeline where the primary hazards are rocks, stumps, and open creeks. We currently have very limited snowpack observations within this region and it is critical to supplement this information with your own observations.