North Columbia

Danger is expected to increase with forecast snow and wind. As always, and especially when forecast confidence is low, it's important to supplement this forecast with your own observations. Please post your obs to the MIN.

Low - Intensity of incoming weather systems is uncertain

A series of storms will bring new snow to the region on Thursday and Friday. The first wave will bring 10-15 cm of fresh snow throughout the day on Thursday with daytime freezing levels around 1200 m and moderate southwesterly winds. The next pulse will start overnight and bring another 15-20 cm on Friday with similar winds and freezing levels. Precipitation and wind will taper off by the weekend with freezing levels dropping to valley bottom.

Several small loose avalanches were reported on Tuesday on steep sun-exposed slopes. A few size 2 slab avalanches have been reported on wind-loaded slopes the past few days. The incoming storms will likely result in larger wind slabs in the upcoming days and larger storm slab avalanches may occur as the storm snow settles into a cohesive slab.

Early season snowpack observations are still limited, but recent reports suggest snowpack depths are 80-150cm at treeline and 140-200cm in the alpine. New snowfall will add to the 40-70cm of storm snow from the previous week and moderate southerly winds will continue to form wind slabs on lee and cross-loaded slopes. The mid-November crust exists 40-70 cm below the surface and may become reactive once the storm snow settles into a cohesive slab. The lower snowpack is moist below the crust and generally well bonded. The snowpack below treeline remains below threshold for avalanches, but watch out for early season hazards such as hidden rocks, stumps, and open creeks.