A significant storm is expected to impact this region on Tuesday night and into Wednesday, resulting in high avalanche danger.
Confidence
Moderate - Intensity of incoming weather systems is uncertain on Wednesday
Weather Forecast
Tonight: 15-25 cm new snow expected, particularly on the eastern side of the range. Moderate easterly winds.Wednesday: a further 15-25 cm new snow expected, again favouring the eastern sides. Moderate northeasterly winds. Treeline temperatures around -9C.Thursday: Mostly dry during the day. Moderate northwesterly winds. Treeline temperatures around -10C.Friday: Light snow, 4-6 cm. Light easterly winds. Treeline temperatures around -12C.
Avalanche Summary
Avalanches are likely to occur on Wednesday in response to forecast heavy snow and strong winds.
Snowpack Summary
Up to 30 cm of recent snow has fallen in conjunction with variable winds. This new snow has fallen on a variety of surfaces including old crusts, wind-scoured surfaces and, in sheltered terrain at and below treeline, very large feathery surface hoar crystals. The two crusts that were buried near the end of November can be found lower in the snowpack. A third crust from the end of October exists near the base of the snowpack. Recent testing on this crust did not produce significant results.
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.