Forecast snowfall amounts are uncertain. If you receive more than 20 cm of new snow, consider the alpine danger rating to be HIGH.
Confidence
Moderate - Forecast snowfall amounts are uncertain
Weather Forecast
The next Pacific frontal system will reach the Interior tonight spreading moderate precipitation amounts through Wednesday. Average snow amounts range from 15-25 cm by Wednesday afternoon, localized amounts could be higher. Ridgetop winds will be moderate-strong from the SW, alpine temperatures -7 and dropping. A split flow in the jet stream will guide subsequent Pacific storms south of B.C. bringing mostly dry and unsettled weather Thursday and Friday. The next storm will move onshore sometime Saturday.
Avalanche Summary
On Monday, numerous small, natural and rider triggered wind slab avalanches up to size 1.5 and widespread loose dry sluffing up to size 1 were reported from the region. With new snow forecast, storm slab avalanches will likely become more of a widespread avalanche problem.
Snowpack Summary
New snow 5-15 cm recently fell over the region, soft storm slabs now overlie a variety of touchy weak layers. Storm and wind slabs will likely continue to build with forecast snow on Wednesday. There is now up to 45 cm sitting on a mix of surface hoar, facets, and sun crusts that were buried January 4th. The mid and lower snowpack are generally well settled and strong.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.