A storm passing through the region today may be more intense than expected. Avalanche danger may rise to High during periods of heavy snowfall and/or high winds. Avoid exposure to avalanche terrain if winds increase or it really starts dumping snow.
Weather Forecast
Avalanche danger will increase today. As a cold front passes through the region winds will increase and steady snow may add up to 20cm of snow by Sunday morning. Precipitation should taper off by Sunday afternoon with possible sunny periods. Monday should be mostly sunny, with cool alpine temperatures and moderate SW'ly winds.
Snowpack Summary
Soft slabs are most cohesive above treeline; a result of southerly winds. A widespread surface hoar layer down 25-40cm is most reactive where it is largest; between 1700-1900m; or on steep solar aspects where it formed over a sun crust. A series of surface hoar and crust layers up to 1m below this layer continue to fail in snowpack tests.
Avalanche Summary
There have been several reports of skiers accidentally triggering avalanches up to size 2 on the most recent surface hoar layer. These have occurred on all aspects and elevations, with the avalanches propagating up to 80m wide and traveling fast and far. Skiers in these areas have reported clues such as cracks shooting up to 80m from their ski tips
Confidence
Timing, track, or intensity of incoming weather system is uncertain
Problems
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind 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.