Dashboard Regions Weather Stations Radar Alerts Glossary
Contact About
Log In

Register for an account and never miss a forecast again!

Register

Avalanche Forecast

Archived

Feb 28th, 2022–Mar 1st, 2022

Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches possible, human triggered probable.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches possible, human triggered probable.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely, human triggered possible.

Regions

Sea To Sky.

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.

Confidence

Moderate - Forecast precipitation (either snow or rain) amounts are uncertain.

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 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.

Loose Wet

Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.