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

Apr 8th, 2023–Apr 9th, 2023

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

Regions

Glacier.

Expect a wintery storm slab in the alpine and spring-like wet snow avalanches at treeline and below.

Re-evaluate your mindset as your travel through different elevation bands- expect variability!

Confidence

Moderate

Avalanche Summary

Several loose moist avalanches and a few cornice failures were observed from steep north aspects today, up to size 2.0.

Thursday, a group boot-packing on Grizzly Mountain triggered a size 2.0 windslab in a variable snowpack depth area.

On Wednesday, a skier triggered, size 1 on a SE aspect in the alpine behind Mt Bonney. This was a thin slab (~15cm) above a crevasse. A natural cornice fall avalanche sz 2.5 also occurred off Mt Bonney, MIN.

Snowpack Summary

Last night ~10cm of new snow fell at treeline and above, and up to 5cm of wet snow fell below treeline. The March 31st is down 20-40cm and is comprised of a solid crust on solar aspects and isolated surface hoar/facets on polar aspects.

The mid and lower snowpack is generally strong. However, the basal weakness from November can still be found near the ground in many locations. Be ready for this layer to wake-up in the next few days.

Weather Summary

An Atmospheric River is poised to arrive Sunday afternoon. The track of this storm is quite uncertain, with forecasted snow amounts for Rogers Pass ranging from 25-45cm by Tuesday morning.

Tonight: Trace of snow. Alpine Low -4 °C. Moderate gusting strong SW wind. FZl 1500m

Sun: Snow 12cm (ramping up in the late afternoon). Alp High -1 °C. Mod gusting strong SW wind, FZL 2000m

Mon: Snow 14cm. Alp Low -5 °C, High -2 °C. Light gusting strong SW wind. FZl 1800m

Terrain and Travel Advice

  • Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
  • Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
  • Be aware of the potential for loose avalanches in steep terrain where snow hasn't formed a slab.

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.