Avalanche Forecast

Archived

Feb 7th, 2024–Feb 8th, 2024

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Regions

Jasper, Brazeau, Churchill, Cirrus-Wilson, Fryatt, Icefields, Maligne, Marmot, Miette Lake, Pyramid.

Even at moderate hazard, big, connected, sunny slopes are concerning, and it may be possible to trigger the basal layers, especially in steep TL features.

Don't ignore the warnings like whumphing or cracking. It remains a weak, winter snowpack with active persistent and deep persistent problems!

Confidence

High

Avalanche Summary

The field team on Monday triggered a sz 1.5 persistent slab on a south asp. at TL in Boundary Lake on the Parkway. Triggered with a whumph and was slow to initiate.

No new avalanches were observed or reported on Wednesday.

Snowpack Summary

A light dusting of recent snow sits over a variable, breakable crust. This crust can seen as a 1-3cm near surface crust on shaded aspects, up to a 15-20cm melt freeze crust observed on solar aspects. Big, connected, and sunny treeline features are the most troublesome. Persistent and deep persistent weak layers remain ever-present and active. Do not trust either of these layers.

Weather Summary

Wednesday Overnight: Clearing. Low in the Icefields: -8°C

Thursday: Mix of Sun and Cloud. Light winds and precipitation. Alpine High -7 °C; Light right top winds. Freezing level: Valley Bottom.

The Mountain Weather Forecast is available at Avalanche Canada https://avalanche.ca/weather/forecast

Terrain and Travel Advice

Avoid shallow snowpack areas, rock outcroppings and steep convex terrain where triggering is most likely.

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.

Deep Persistent Slabs

Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.