The February 12th surface hoar is the main concern, and is most reactive in areas at and below treeline where it sits on a sun crust, or has been undisturbed by skier traffic. Be cautious venturing into new or previously unridden terrain.
Weather Forecast
Mostly dry until Friday, when warm temps and moderate precipitation should carry the scent of pineapples from Hawaii. Winds are forecast to be light today with some gusty conditions up to 50kph and light Thursday morning, then rise to high on Thursday afternoon heralding the storm on Friday.
Snowpack Summary
Top 30 cm of settling storm snow with a soft breakable crust on top where it is exposed to the sun. Feb 12 surface hoar and crust layers down 40-55 cm. Mid pack is well settled.
Avalanche Summary
Recent avalanche control west of Rogers Pass summit produced 4, size 3.0 avalanches and 4, size 2.0-2.5.One natural avalanche was recorded yesterday, East of the summit, a small size 1.5, from a wind loaded start zone which ran to 2/3 path, on a North aspect.
Confidence
Timing, track, or intensity of incoming weather system is uncertain on Friday
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.
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.