Avalanche Forecast

Moderate -

The low that recently delivered significant wind, snow and rain to the interior is expected to weaken on Friday resulting in less frequent and less intense convective flurries. Saturday offers a brief lull in the action before another system takes aim at the interior Sunday.FRIDAY: Scattered cloud cover, freezing level beginning at valley bottom rising to around 1000 m in the afternoon, moderate southwest wind, 1 to 3 cm of snow possible.SATURDAY: Scattered cloud cover, freezing level holding near valley bottom, light south/southwest wind, 1 to 5 cm of snow possible. SUNDAY: Scattered cloud cover, freezing level holding near valley bottom, moderate to strong southerly wind, 1 to 5 cm of snow possible.

On Wednesday a small natural avalanche cycle was reported from steep ridge features. Fast and loose sluffing was also reported. No new avalanche activity to report from Tuesday.On Monday warm temperatures and direct solar induced natural persistent slab avalanches to size 3.0 on solar aspects between 1600 and 2600 m. Loose wet avalanches were reported from all aspects to size 2.0. On Sunday loose avalanches were reported from all aspects to size 1.0. On Southwest, south and southeast facing terrain between 1500 m and 2700 m, loose wet avalanches to size 2.5 and persistent slab avalanches to size 2.0 were reported to have failed naturally. A small wind slab was human triggered on a north facing feature just below ridge crest. On Saturday natural avalanches up to size 2.5 were reported on northeast facing features between 1200 m and 1500 m. One small skier triggered avalanche was remotely triggered on a moderately inclined northeast facing alpine feature.

The current snowpack is complex, we now have three active Persistent Weak Layers (PWL) that we are monitoring. Wednesday and Thursday's highly convective storm left 10 to 20 cm in its wake. This snow buried the mid-January PWL that is a crust and/or surface hoar interface. Prior to Wednesday's storm the crust was reportedly widespread, high elevation north is likely one of the few crust-free zones. The now buried surface hoar is up to 10 mm in size and was reportedly present at all elevations before the storm.  The second PWL is known as the early January interface, it is 30 to 60 cm below the surface. It is composed of surface hoar on sheltered slopes as well as sun crust on steep solar aspects and is present at all elevation bands. Recent snowpack tests have shown sudden results with moderate loads.The third PWL is the mid-December facet/surface hoar/crust combination that is now buried 80 to 100 cm deep and is most problematic at and below treeline. This interface is not thought to be present in the alpine.The November rain crust is 100 to 150 cm deep and is thought to have gone dormant for the time being.