Avalanche Forecast
Issued: Feb 28th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Loose Wet.
ahanna,
Avalanche Canada
New snow and wind continue to build reactive storm slabs at upper elevations. Loose wet avalanches will become increasingly likely as rain soaks the surface snow below 1400 m.
Summary
Confidence
Weather Forecast
Monday night: 10-15 cm new snow, moderate southwest wind, alpine temperature -1 C, freezing level 1500 m.
Tuesday: 5-10 cm new snow, moderate southwest wind, alpine temperature -1 C, freezing level 1400 m.
Wednesday: 15-25 cm new snow, wind easing to light south, alpine temperature -1 C, freezing level 1200-1500 m.
Thursday: Clearing, light northwest wind, alpine temperature -1 C, freezing level 1000-1500 m.
Avalanche Summary
Storm slabs were touchy on Sunday! Skier and explosive control work produced size 1-2 avalanches, a number of them remotely or sympathetically triggered. This MIN report describes a remotely triggered size 1 on a convex roll in an open area below treeline.
By Monday, storm slabs were still reactive but less electric. A natural cycle up to size 2 was observed through limited visibility in the Whistler backcountry. Explosive control work produced mostly size 1s with a couple size 2 storm slabs. On the other side of the 99, a size 1 wet slab was observed sliding on the crust on an east aspect at 1500 m.
Snowpack Summary
20-50 cm of wind affected, upside-down storm snow sits over a variety of surfaces including sun crusts on solar aspects, a thick rain crust in windswept terrain and facets in shady, sheltered terrain. The upper snowpack is moist or wet below 1400 m.
A crust/facet/surface hoar interface formed late-January is buried down 40-100 cm. This layer was most reactive between 1700 m and 2000 m. While this layer has been dormant in most of the region lately, large loads such as heavy snowfalls and cornice falls could wake it up and produce very large avalanches.
Terrain and Travel
- Minimize exposure during periods of heavy loading from new snow, wind or rain.
- Watch for fresh storm slabs building throughout the day.
- Keep in mind that wet avalanches can be destructive due to their high density.
Problems
Storm Slabs
Storm slabs will continue to develop throughout the day where precipitation falls as snow. The new snow does not appear to be bonding well to underlying surfaces in many areas. Storm slabs are especially likely to be triggered in steep or convex terrain and in wind loaded areas.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Loose Wet
Loose wet avalanches will become increasingly likely as rain soaks the surface snow below 1400 m.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Valid until: Mar 1st, 2022 4:00PM
