Avalanche Forecast

Issued: Mar 2nd, 2022 4:00PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is considerable. Known problems include Storm Slabs, Wet Slabs and Loose Wet.

Avalanche Canada swerner, Avalanche Canada

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Reactive storm slabs exist at higher elevations. At lower elevations, loose wet and wet slab avalanches are likely.

The danger rating reflects the forecast for the Southern part of the region. Elsewhere, avalanche danger may be a step lower.

Summary

Confidence

Moderate - Uncertainty is due to how quickly the snowpack will recover and gain strength.

Weather Forecast

Change is in the air with an unstable airmass bringing convective, spring-like weather. Generally, overcast skies and a drying trend will exist Thursday. The ridge should be set up by Friday with clearing skies and light northwest winds.   

Wednesday Night: 5-10 cm of new snow. Freezing levels dropping to 1000 m overnight and moderate southwesterly wind at ridgetop. 

Thursday: Cloudy skies in the South with possible periods of sunshine in the North. Convective flurries up to 10 cm with light northwest wind. Freezing levels 1000 to 1500 m. 

Friday: Sunny skies with spring-like (diurnal) freezing levels dropping to 1000 m overnight and rising to 1500 m during the day. Ridgetop wind moderate from the northwest. 

Avalanche Summary

On Wednesday, numerous storm slab and loose wet avalanches up to size 2 were reported. Treeline and below treeline terrain saw wet loose avalanches up to size 2 as well. 

On Tuesday afternoon, reports from the southern part of the region saw a widespread natural wet loose and wet slab cycle up to size 3. A few glide slab releases also occurred up to size 1.5. These avalanches may have actually occurred on Monday. In the northern part of the region, snowballing was seen from below treeline elevations. No new reports from the southern half of the region. 

Snowpack Summary

Anywhere from 40 cm to 60 cm of recent storm snow has accumulated in the North (Pemberton area) and up t 80 cm in the South (Coquihalla) over a variety of surfaces that were buried mid-February. These old interfaces include surface hoar and/or facets in shady, wind-sheltered areas, sun crust on solar aspects, and hard wind slab in the alpine. Generally, the storm snow seems to be settling quickly, however, deeper deposits have formed thicker slabs on leeward slopes treeline and above. The snow is becoming moist/wet and rain-soaked at lower elevations. 

Another crust/facet layer from late-January is buried down 40-120 cm and has shown no results in recent snowpack tests and is dormant at this time.

Terrain and Travel

  • Storm snow and wind is forming touchy slabs. Use caution in lee areas in the alpine and treeline.
  • Don't be too cavalier with decision making, storm slabs may remain sensitive to human triggering.
  • Watch for unstable snow on specific terrain features, especially when the snow is moist or wet.
  • Keep in mind that wet avalanches can be destructive due to their high density.

Problems

Storm Slabs

An icon showing Storm Slabs

40 to 60 cm in the North and up to 80 cm in the South of recent storm snow has blanketed upper elevations. The likelihood of triggering storm slabs increases in steep or convex terrain and in wind loaded areas.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2.5

Wet Slabs

An icon showing Wet Slabs

Continued rain and higher freezing levels are making the upper snowpack very unstable. Wet slabs are releasing easily and sliding on a firm melt-freeze crust buried below. Reports indicate this is specific to the Southern half of the region. 

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Possible

Expected Size

1.5 - 2.5

Loose Wet

An icon showing Loose Wet

Loose wet avalanches are possible from steeper terrain features at treeline and below treeline. Brief periods of sunshine may easily trigger loose wet avalanches at all elevations on southerly facing slopes.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Mar 3rd, 2022 4:00PM