Conditions have changed dramatically. There is significant variability from west to east in the region. Be locally aware as to the amount of new snow and how it is bonding to the underlying surfaces.
Confidence
Fair - Forecast snowfall amounts are uncertain
Weather Forecast
Monday: Expect clouds to build with precipitation beginning in the afternoon and continuing through the evening. Up to 15cm are possible. Temperatures should reach -8 with light west winds.Tuesday: Flurries are possible with light accumulations and temperatures of -10. Winds stay westerly but increase through the day before easing overnight.Wednesday: Another wave of precipitation with accumulations of 25cm possible. Winds turn southerly with temperatures reaching -7.
Avalanche Summary
Small windslabs up to size 1.5 have been reported, failing in immediate lee locations of ridgelines. Sluffing up to size 1.5 continues.
Snowpack Summary
On the west side of the region up to 30cm of low density new snow overlies the January 4th interface while on the east side the new snow totals around 10cm. Moderate and strong south/southwest winds have redistributed this new snow into small windslabs in immediate lee features in the alpine and exposed treeline and these windslabs are reactive to human triggering.The January 4th interface consists predominantly of loose facets up to 30cm deep. In isolated locations (sheltered treeline and below treeline) surface hoar is present and there is a sun crust on steep south and west facing terrain. High in the alpine in exposed locations, old windslabs linger. The new snow is bonding poorly to these interfaces, and lots of sluffing is being reported. Where the storm snow is deeper, the sluffing is extensive enough to require a management plan.The midpack is well bonded and strong. The deep crust/facet combo from early November still exists and concern remains (although unlikely) for triggering this layer from a shallow spot.
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.
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.