Kootenay Boundary

Fair - Timing, track, or intensity of incoming weather system is uncertain on Friday

Tonight and Friday: The next system should move inland during the day bringing moderate precipitation easing during the day Friday (expect between 10 and 20 cm). Winds will pick up again blowing moderate to strong from the southwest. Freezing levels should rise to around 1300 m during the day.Saturday: A building ridge before the next system should keep the region dry during the day. Winds should start to pick up from the southwest as the next system nears in the evening as well as rising freezing levels.Sunday: The system is expected to bring more light to moderate amounts of precipitation with similar winds and temperatures.

There was an avalanche cycle yesterday; multiple natural slab avalanche up to size 2.5 and numerous skier triggered avalanches up to size 2 were reported. Some ran on the late January melt freeze crust on east aspects and some on the new surface hoar layer that just got buried with the recent storm.

10-20 cm of new snow is expected to fall during the day tomorrow which will sit the recent ~30 cm. Moderate to strong winds will keep developing windslabs on lee slopes likely producing large natural avalanches on east and northeast aspects in the alpine and at treeline. Rising temperatures during the day could also promote slab formation and weaken the storm snow on all aspects.The storm snow is sitting on a variety of weak layers that formed during the recent cold snap; surface facets, a new surface hoar layer on shady aspects, a crust on solar aspects or hard windslabs in the alpine. 40-60 cm below the surface, exists a surface hoar or suncrust layer has been reactive to skier traffic even since it has been buried in late January. Natural and skier triggered avalanches have stepped down to this deeper buried weak layer in the recent avalanche cycle. This layer has now reached a critical load where big destructive avalanches can be easily triggered.The mid snowpack is strong and supportive. Deeper persistent layers have been dormant, however, they could wake up in the near future with the increasing load.