Regions
South Coast Inland.
Wind slabs in the alpine and treeline are the primary concern. Expect the temperature to fall as cold air invades from the north.
Confidence
Moderate - Due to the number of field observations
Weather Forecast
SATURDAY Night: Mainly cloudy, light to moderate east wind, alpine temperature -15 C.SUNDAY: Mainly cloudy with scattered flurries, moderate northeast wind, alpine temperature -17 C.MONDAY: Mix of sun and cloud, moderate northeast wind, alpine temperature -19 C.TUESDAY: Mix of sun and cloud, light northeast wind, alpine temperature -13 C.
Avalanche Summary
No avalanches were reported in the region on Friday or Saturday.
Snowpack Summary
15-30 cm of new snow with moderate southwesterly winds is sitting on a crust on all but northerly aspects, wind-affected surfaces in the alpine, and possibly a mixture of weak feathery surface hoar and/or sugary facets in sheltered terrain at treeline and below.A crust that recently formed right to mountain top on southerly aspects and on all aspects below 1700 m is now buried 50-80 cm deep. Additionally at this depth, feathery surface hoar may be found in shady sheltered areas at treeline. The remainder of the snowpack is generally well-settled and strong.
Problems
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.
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.