New snow and strong wind will create dangerous avalanche conditions.
New snow and strong southwest wind will form unstable storm slabs. Slab formation is most likely in wind-drifted areas. There is uncertainty about how well these slabs will bond to underlying interfaces.
Friday night: Cloudy, scattered flurries with trace accumulations, moderate to strong southwest wind, freezing level dropping to 1200 m, alpine temperatures reach -4 C.
Saturday: Cloudy, 10-20 cm of new snow, moderate southwest wind gusting strong at ridge-tops, freezing level climbing to 1600 m in the afternoon, alpine temperatures reach -2 C.
Sunday: Cloudy, 5-15 cm of new snow, moderate southwest wind gusting strong at ridge-tops, freezing level climbing to 1400 m in the afternoon, alpine temperatures reach -6 C.
Monday: Cloudy, 5-15 cm of new snow, moderate southwest wind, freezing level climbing to 1200 m in the afternoon, alpine temperatures reach -6 C.
No recent avalanches have been reported, but mountain travel and field observations have been very limited over the past few days. Last week there were many wet loose avalanches and some large glide slabs, but cooler weather and new snow has made storm slabs the main concern.
Periods of heavy snow with strong southwest winds are expected to build widespread, reactive storm slabs and create dangerous avalanche conditions.
Snowfall from earlier in the week was highly variable across the region with some areas receiving 15-25 cm and adjacent valleys getting as little as 0-5 cm. Some of the heavier accumulations fell in the south part of the region. This snow covered a variety of previous snow surfaces including crusts, warm snow, and wind-affected snow. It may also sit above some small surface hoar on shaded, sheltered slopes. Overall, there is some uncertainty about how well the snow has bonded to these interfaces.
Northern parts of the region have had a deep instability lingering at the base of the snowpack for most of the season, however this layer has gained strength over the past month (with the last reported avalanche on Feb 17).
