Cooler temperatures are expected tomorrow and as a result, we expect natural avalanche activity to begin to decrease. Lots of skier triggerred avalanches and remote triggerred avalanches have been observed of late so use caution.
Weather Forecast
Freezing levels are forecast to drop back to valley floors over the next few days and winds are expected to remain calm. No new snow is expected but there is forecast to be a mix of sun and cloud. The solar radiation is intense at this time of year so pay close attention your aspect in relation to the sun.
Avalanche Summary
A few new avalanches were observed on Sunday at treeline elevations and below. The failure plain for the majority of these avalanches was likely the 0211 interface down on average 80-100cm.
Snowpack Summary
Freezing levels remained around 1900m on Sunday with rain below this elevation and wet snow above. The snowpack below here is now becoming isothermal in some areas. Above this elevation, the wet heavy snow continued to release natural avalanche up to sz 2.5 at treeline and below. The drier snow in Alpine areas was being redistributed by strong SW flow onto lee aspects building new storm slabs.
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.
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.