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 1st, 2023–Jan 2nd, 2023

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

Regions

Glacier.

We are entering a period where avalanche activity will taper off, and the chance of triggering a buried weak layer becomes less likely. However, if triggered, the avalanche could be large and destructive. Choose low-consequence terrain features and manage your group appropriately.

High-quality, deep pow can be found throughout the Park.

Confidence

Moderate

Avalanche Summary

On Sunday several size 2-2.5 storm slab avalanches were observed from steep, wind-loaded terrain, and several size 1-1.5 dry loose avalanches from steep and rocky solar aspects.

Reports of human-triggered storm slab up to size 1.5 from the past few days from ridgeline start zones and steep unsupported terrain features.

Snowpack Summary

The top 30cm of snow is low-density and provides great powder turns. The Dec 23 facet interface is down ~70cm but is rounding and gaining strength. The Dec 5 and Nov 17 surface hoar layers have been less reactive recently but had been exhibiting 'sudden' results in snowpack tests.

Weather Summary

A ridge of high pressure persists in the area and will bring a mix of sun and cloud, light ridgetop winds, and temperatures ranging from -4 to -10.

Small amounts of snow are in the forecast for Friday.

Terrain and Travel Advice

  • Continue to make conservative terrain choices while the storm snow settles and stabilizes.
  • Avoid convexities, steep unsupported terrain and rocky outcroppings.
  • If triggered, loose dry avalanches may step down to deeper layers resulting in large avalanches.
  • Back off if you encounter whumpfing, hollow sounds, or shooting cracks.

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.

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.

Loose Dry

Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.