Avalanche Forecast

Archived

Mar 29th, 2025–Mar 30th, 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 possible, human triggered probable.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Regions

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

Sunny skies and clear weather this weekend may be inviting, but don't let your guard down. Recent snow, sun and warm temps continue to stress the snowpack.

Deeper instabilities and persistent weak layers remain reactive. Give the snowpack time to recover, stick to conservative terrain, and avoid overhead hazard.

Confidence

Moderate

Avalanche Summary

Road patrol on the Icefields Parkway observed numerous wet loose avalanches up to size 1 occurring immediately after the sun appeared. A natural size 2.5 deep persistent slab was seen on a north aspect in the Parkers area, along with several new size 2 persistent slabs, also triggered by solar warming.

Recent snow and warm temperatures continue to drive daily natural avalanche activity at treeline and below. Poor visibility has limited alpine observations this week.

Snowpack Summary

Up to 10 cm of moist surface snow is present up to 2300 m. The upper snowpack consists of up to 25 cm of new snow from this week, which is settling rapidly and sits atop newly formed crusts from recent snow, warming and/or rain. A 50-100 cm settled mid-pack rests over the March and January facet interfaces. The lower snowpack remains weak, with depth hoar and old crusts. Snow depth at treeline ranges from 110 to 170 cm.

Weather Summary

Sunday

A mix of sun and cloud. Alpine temperature: High -3 °C. Ridge wind light to 20 km/h. Freezing level: 1900 metres.

Monday

A mix of sun and cloud. Alpine temperature: Low -9 °C, High -1 °C. Ridge wind light to 15 km/h. Freezing level: 2000 metres.

Tuesday

A mix of sun and cloud with isolated flurries. Alpine temperature: Low -6 °C, High -2 °C. Ridge wind light to 20 km/h. Freezing level: 2000 metres.

Terrain and Travel Advice

Make conservative terrain choices and avoid overhead hazard.
Even brief periods of direct sun could produce natural avalanches.
A moist or wet snow surface, pinwheeling, and natural avalanches are all indicators of a weakening snowpack.
Loose avalanches may step down to deeper layers, resulting in larger avalanches.

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.

Loose Wet

Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.