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

Jan 15th, 2025–Jan 16th, 2025

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

Regions

Northwest Coastal, Boundary, Stewart, Ningunsaw, Ningunsaw, Ningunsaw.

Deep instabilities are present and have produced large avalanches during the storm. The recent storm snow will need time to settle and stabilize, and human triggering is likely.

Confidence

Moderate

Avalanche Summary

On Tuesday, numerous naturally triggered persistent slab avalanches (up to size 3) were reported. A skier remotely triggered a size 1.5 persistent slab from 50 m away.

Natural avalanche activity may taper but human-triggered avalanches are likely on Thursday.

Snowpack Summary

Another 30 + cm is expected Wednesday bringing storm snow totals up to 80 cm over the past few days. Strong to extreme west through southwest wind has created widespread wind effect, with deeper deposits of snow on leeward slopes.

Down 70 to 120 cm a layer of surface hoar, facets, or a thin crust exists.

A persistent weak layer of surface hoar and facets overlying a crust is buried 120 to 150 cm deep. This layer remains reactive, producing large and dangerous avalanches.

Weather Summary

Wednesday Night

Snow 10 cm. 30 to 60 km/h southwest ridgetop wind. Treeline temperature -5 °C. Freezing level 700 m.

Thursday

Snow 5 to 10 cm. 20 to 50 km/h southwest ridgetop wind. Treeline temperature -6 °C. Freezing level valley bottom.

Friday

A mix of sun and cloud, possible flurries up to 5 cm. 25 to 50 km/h northwest ridgetop wind. Treeline temperature -9 °C. Freezing level valley bottom.

Saturday

Cloudy. 10 to 30 km/h north ridgetop wind. Treeline temperature -8 °C. Freezing level valley bottom.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Fresh snow rests on a problematic persistent slab, don't let good riding lure you into complacency.
  • Storm slabs in motion may step down to deeper layers resulting in large avalanches.
  • Avoid freshly wind-loaded terrain features.
  • Keep in mind that human triggering may persist as natural avalanches taper off.

Problems

Persistent Slabs

Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.

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.