North Columbia

Consider avalanche danger to be HIGH in areas that receive rain on top of 30 cm or more of dry snow. Avoid exposure to avalanche terrain during periods of rapid loading by rain, snow, or wind.

Low - Timing, track, or intensity of incoming weather system is uncertain

We should see a return to more seasonal temperatures this week with small accumulations of snow. MONDAY: Cloudy with isolated flurries. Light to moderate westerly ridgetop winds. Freezing level around 1000 mTUESDAY: 5-10 cm of snow. Light to moderate westerly ridgetop winds. Freezing level around 1500 mWEDNESDAY: Isolated flurries. Moderate westerly ridgetop winds. Freezing level rising around 1200 m

On Saturday we received reports of a skier-triggered Size 1 storm slab on a NW aspect at 2150m elevation in Rogers Pass. See here for the MIN report. A natural avalanche cycle is expected on Sunday into early Monday in areas where rain falls on dry snow. We currently have very limited observations in this region. Please submit your observations to the Mountain Information Network (MIN).

15 to 30 cm of recent snow and moderate to strong southwesterly winds have likely formed wind slabs on lee features at treeline and above. The new snow sits on a thick crust formed by the rain that fell to mountain tops last Wednesday and Thursday. The heavy rains of last week rapidly shrunk the snowpack and has transitioned much of the snowpack from dry to moist snow. The depth of the snowpack varies greatly with elevation. Recent reports suggest the average depth is 200+cm in the alpine, 100-150cm at treeline, and decreasing rapidly below treeline where the primary hazards are rocks, stumps, and open creeks. A major feature in the snowpack is a crust which was formed around Halloween and can be found approximately 70-100cm down at treeline elevations. We currently have very limited snowpack observations within this region and it is critical to supplement this information with your own observations.