Avalanche Forecast
Issued: Jan 31st, 2017 4:20PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
rbuhler,
Avalanche Canada
Lingering wind slabs are expected to remain reactive in steep wind loaded terrain features. Use extra caution as you transition into wind affected terrain and watch for signs of recent wind loading.
Summary
Confidence
Moderate - Wind effect is extremely variable
Weather Forecast
A ridge of high pressure keeps the region cold and dry for the next few days. Wednesday and Thursday are expected to sunny with light northeast wind and treeline temperatures around -15C. Increasing cloud cover is expected on Friday in advance of a weak storm system which is currently forecast to arrive late Friday.
Avalanche Summary
On Monday, several natural wind slab avalanches up to size 2 were observed throughout the region. These avalanches occurred on most aspects and were mainly in the alpine. Skiers also triggered several wind slab avalanches on Monday up to size 1.5. On Sunday, a natural size 1.5 wind slab avalanche was reported near Invermere on a northwest aspect at 2600 m elevation which had a slab thickness of 50 cm. In the Dogtooth, a few small natural wind slab avalanches were observed which were 5-15 cm thick. A MIN report from the Quartz Creek area shows a sledder triggered size 2 wind slab avalanche. Click here for more details. On Wednesday, recently formed wind slabs are expected to remain reactive to human triggering, especially on steep and unsupported or convex slopes. Winds have recently switched from south to north and wind slabs should be expected on all aspects.
Snowpack Summary
5-20cm of recent new snow with strong shifting winds have formed wind slabs on a variety of aspects in wind exposed terrain. A sun crust is being reported on steep solar aspects. Surface faceting is also being reported as a result of the current cold temperatures. The mid-January interface is now down 20-50 cm and consists of buried surface hoar in sheltered areas, old wind slabs in exposed terrain, and/or widespread faceted old snow. The interface has generally stabilized but isolated weaknesses may still exist where buried surface hoar is preserved. The mid-December surface hoar/facet weakness from is down 50-100 cm and is generally considered dormant. However, a few storm slab and wind slab avalanches stepped down to this layer last week in isolated areas. This layer remains an isolated concern for shallow snowpack areas where the weakness is closer to the snow surface.
Problems
Wind Slabs
Recently formed wind slabs are expected to remain reactive in steep terrain. Recent winds have been from a variety of directions and wind slabs should be expected on all aspects in wind exposed terrain.
Avoid areas where the surface snow feels stiff or slabby.Use caution in lee areas. Recent wind loading has created wind slabs.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 1st, 2017 2:00PM
